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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 *******************************************************************************
5 *
6 *   Copyright (C) 2009-2014, International Business Machines
7 *   Corporation and others.  All Rights Reserved.
8 *
9 *******************************************************************************
10 *   file name:  normalizer2impl.cpp
11 *   encoding:   UTF-8
12 *   tab size:   8 (not used)
13 *   indentation:4
14 *
15 *   created on: 2009nov22
16 *   created by: Markus W. Scherer
17 */
18 
19 // #define UCPTRIE_DEBUG
20 
21 #include "unicode/utypes.h"
22 
23 #if !UCONFIG_NO_NORMALIZATION
24 
25 #include "unicode/bytestream.h"
26 #include "unicode/edits.h"
27 #include "unicode/normalizer2.h"
28 #include "unicode/stringoptions.h"
29 #include "unicode/ucptrie.h"
30 #include "unicode/udata.h"
31 #include "unicode/umutablecptrie.h"
32 #include "unicode/ustring.h"
33 #include "unicode/utf16.h"
34 #include "unicode/utf8.h"
35 #include "bytesinkutil.h"
36 #include "cmemory.h"
37 #include "mutex.h"
38 #include "normalizer2impl.h"
39 #include "putilimp.h"
40 #include "uassert.h"
41 #include "ucptrie_impl.h"
42 #include "uset_imp.h"
43 #include "uvector.h"
44 
45 U_NAMESPACE_BEGIN
46 
47 namespace {
48 
49 /**
50  * UTF-8 lead byte for minNoMaybeCP.
51  * Can be lower than the actual lead byte for c.
52  * Typically U+0300 for NFC/NFD, U+00A0 for NFKC/NFKD, U+0041 for NFKC_Casefold.
53  */
leadByteForCP(UChar32 c)54 inline uint8_t leadByteForCP(UChar32 c) {
55     if (c <= 0x7f) {
56         return (uint8_t)c;
57     } else if (c <= 0x7ff) {
58         return (uint8_t)(0xc0+(c>>6));
59     } else {
60         // Should not occur because ccc(U+0300)!=0.
61         return 0xe0;
62     }
63 }
64 
65 /**
66  * Returns the code point from one single well-formed UTF-8 byte sequence
67  * between cpStart and cpLimit.
68  *
69  * Trie UTF-8 macros do not assemble whole code points (for efficiency).
70  * When we do need the code point, we call this function.
71  * We should not need it for normalization-inert data (norm16==0).
72  * Illegal sequences yield the error value norm16==0 just like real normalization-inert code points.
73  */
codePointFromValidUTF8(const uint8_t * cpStart,const uint8_t * cpLimit)74 UChar32 codePointFromValidUTF8(const uint8_t *cpStart, const uint8_t *cpLimit) {
75     // Similar to U8_NEXT_UNSAFE(s, i, c).
76     U_ASSERT(cpStart < cpLimit);
77     uint8_t c = *cpStart;
78     switch(cpLimit-cpStart) {
79     case 1:
80         return c;
81     case 2:
82         return ((c&0x1f)<<6) | (cpStart[1]&0x3f);
83     case 3:
84         // no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar)
85         return (UChar)((c<<12) | ((cpStart[1]&0x3f)<<6) | (cpStart[2]&0x3f));
86     case 4:
87         return ((c&7)<<18) | ((cpStart[1]&0x3f)<<12) | ((cpStart[2]&0x3f)<<6) | (cpStart[3]&0x3f);
88     default:
89         UPRV_UNREACHABLE;  // Should not occur.
90     }
91 }
92 
93 /**
94  * Returns the last code point in [start, p[ if it is valid and in U+1000..U+D7FF.
95  * Otherwise returns a negative value.
96  */
previousHangulOrJamo(const uint8_t * start,const uint8_t * p)97 UChar32 previousHangulOrJamo(const uint8_t *start, const uint8_t *p) {
98     if ((p - start) >= 3) {
99         p -= 3;
100         uint8_t l = *p;
101         uint8_t t1, t2;
102         if (0xe1 <= l && l <= 0xed &&
103                 (t1 = (uint8_t)(p[1] - 0x80)) <= 0x3f &&
104                 (t2 = (uint8_t)(p[2] - 0x80)) <= 0x3f &&
105                 (l < 0xed || t1 <= 0x1f)) {
106             return ((l & 0xf) << 12) | (t1 << 6) | t2;
107         }
108     }
109     return U_SENTINEL;
110 }
111 
112 /**
113  * Returns the offset from the Jamo T base if [src, limit[ starts with a single Jamo T code point.
114  * Otherwise returns a negative value.
115  */
getJamoTMinusBase(const uint8_t * src,const uint8_t * limit)116 int32_t getJamoTMinusBase(const uint8_t *src, const uint8_t *limit) {
117     // Jamo T: E1 86 A8..E1 87 82
118     if ((limit - src) >= 3 && *src == 0xe1) {
119         if (src[1] == 0x86) {
120             uint8_t t = src[2];
121             // The first Jamo T is U+11A8 but JAMO_T_BASE is 11A7.
122             // Offset 0 does not correspond to any conjoining Jamo.
123             if (0xa8 <= t && t <= 0xbf) {
124                 return t - 0xa7;
125             }
126         } else if (src[1] == 0x87) {
127             uint8_t t = src[2];
128             if ((int8_t)t <= (int8_t)0x82u) {
129                 return t - (0xa7 - 0x40);
130             }
131         }
132     }
133     return -1;
134 }
135 
136 void
appendCodePointDelta(const uint8_t * cpStart,const uint8_t * cpLimit,int32_t delta,ByteSink & sink,Edits * edits)137 appendCodePointDelta(const uint8_t *cpStart, const uint8_t *cpLimit, int32_t delta,
138                      ByteSink &sink, Edits *edits) {
139     char buffer[U8_MAX_LENGTH];
140     int32_t length;
141     int32_t cpLength = (int32_t)(cpLimit - cpStart);
142     if (cpLength == 1) {
143         // The builder makes ASCII map to ASCII.
144         buffer[0] = (uint8_t)(*cpStart + delta);
145         length = 1;
146     } else {
147         int32_t trail = *(cpLimit-1) + delta;
148         if (0x80 <= trail && trail <= 0xbf) {
149             // The delta only changes the last trail byte.
150             --cpLimit;
151             length = 0;
152             do { buffer[length++] = *cpStart++; } while (cpStart < cpLimit);
153             buffer[length++] = (uint8_t)trail;
154         } else {
155             // Decode the code point, add the delta, re-encode.
156             UChar32 c = codePointFromValidUTF8(cpStart, cpLimit) + delta;
157             length = 0;
158             U8_APPEND_UNSAFE(buffer, length, c);
159         }
160     }
161     if (edits != nullptr) {
162         edits->addReplace(cpLength, length);
163     }
164     sink.Append(buffer, length);
165 }
166 
167 }  // namespace
168 
169 // ReorderingBuffer -------------------------------------------------------- ***
170 
ReorderingBuffer(const Normalizer2Impl & ni,UnicodeString & dest,UErrorCode & errorCode)171 ReorderingBuffer::ReorderingBuffer(const Normalizer2Impl &ni, UnicodeString &dest,
172                                    UErrorCode &errorCode) :
173         impl(ni), str(dest),
174         start(str.getBuffer(8)), reorderStart(start), limit(start),
175         remainingCapacity(str.getCapacity()), lastCC(0) {
176     if (start == nullptr && U_SUCCESS(errorCode)) {
177         // getBuffer() already did str.setToBogus()
178         errorCode = U_MEMORY_ALLOCATION_ERROR;
179     }
180 }
181 
init(int32_t destCapacity,UErrorCode & errorCode)182 UBool ReorderingBuffer::init(int32_t destCapacity, UErrorCode &errorCode) {
183     int32_t length=str.length();
184     start=str.getBuffer(destCapacity);
185     if(start==NULL) {
186         // getBuffer() already did str.setToBogus()
187         errorCode=U_MEMORY_ALLOCATION_ERROR;
188         return FALSE;
189     }
190     limit=start+length;
191     remainingCapacity=str.getCapacity()-length;
192     reorderStart=start;
193     if(start==limit) {
194         lastCC=0;
195     } else {
196         setIterator();
197         lastCC=previousCC();
198         // Set reorderStart after the last code point with cc<=1 if there is one.
199         if(lastCC>1) {
200             while(previousCC()>1) {}
201         }
202         reorderStart=codePointLimit;
203     }
204     return TRUE;
205 }
206 
equals(const UChar * otherStart,const UChar * otherLimit) const207 UBool ReorderingBuffer::equals(const UChar *otherStart, const UChar *otherLimit) const {
208     int32_t length=(int32_t)(limit-start);
209     return
210         length==(int32_t)(otherLimit-otherStart) &&
211         0==u_memcmp(start, otherStart, length);
212 }
213 
equals(const uint8_t * otherStart,const uint8_t * otherLimit) const214 UBool ReorderingBuffer::equals(const uint8_t *otherStart, const uint8_t *otherLimit) const {
215     U_ASSERT((otherLimit - otherStart) <= INT32_MAX);  // ensured by caller
216     int32_t length = (int32_t)(limit - start);
217     int32_t otherLength = (int32_t)(otherLimit - otherStart);
218     // For equal strings, UTF-8 is at least as long as UTF-16, and at most three times as long.
219     if (otherLength < length || (otherLength / 3) > length) {
220         return FALSE;
221     }
222     // Compare valid strings from between normalization boundaries.
223     // (Invalid sequences are normalization-inert.)
224     for (int32_t i = 0, j = 0;;) {
225         if (i >= length) {
226             return j >= otherLength;
227         } else if (j >= otherLength) {
228             return FALSE;
229         }
230         // Not at the end of either string yet.
231         UChar32 c, other;
232         U16_NEXT_UNSAFE(start, i, c);
233         U8_NEXT_UNSAFE(otherStart, j, other);
234         if (c != other) {
235             return FALSE;
236         }
237     }
238 }
239 
appendSupplementary(UChar32 c,uint8_t cc,UErrorCode & errorCode)240 UBool ReorderingBuffer::appendSupplementary(UChar32 c, uint8_t cc, UErrorCode &errorCode) {
241     if(remainingCapacity<2 && !resize(2, errorCode)) {
242         return FALSE;
243     }
244     if(lastCC<=cc || cc==0) {
245         limit[0]=U16_LEAD(c);
246         limit[1]=U16_TRAIL(c);
247         limit+=2;
248         lastCC=cc;
249         if(cc<=1) {
250             reorderStart=limit;
251         }
252     } else {
253         insert(c, cc);
254     }
255     remainingCapacity-=2;
256     return TRUE;
257 }
258 
append(const UChar * s,int32_t length,UBool isNFD,uint8_t leadCC,uint8_t trailCC,UErrorCode & errorCode)259 UBool ReorderingBuffer::append(const UChar *s, int32_t length, UBool isNFD,
260                                uint8_t leadCC, uint8_t trailCC,
261                                UErrorCode &errorCode) {
262     if(length==0) {
263         return TRUE;
264     }
265     if(remainingCapacity<length && !resize(length, errorCode)) {
266         return FALSE;
267     }
268     remainingCapacity-=length;
269     if(lastCC<=leadCC || leadCC==0) {
270         if(trailCC<=1) {
271             reorderStart=limit+length;
272         } else if(leadCC<=1) {
273             reorderStart=limit+1;  // Ok if not a code point boundary.
274         }
275         const UChar *sLimit=s+length;
276         do { *limit++=*s++; } while(s!=sLimit);
277         lastCC=trailCC;
278     } else {
279         int32_t i=0;
280         UChar32 c;
281         U16_NEXT(s, i, length, c);
282         insert(c, leadCC);  // insert first code point
283         while(i<length) {
284             U16_NEXT(s, i, length, c);
285             if(i<length) {
286                 if (isNFD) {
287                     leadCC = Normalizer2Impl::getCCFromYesOrMaybe(impl.getRawNorm16(c));
288                 } else {
289                     leadCC = impl.getCC(impl.getNorm16(c));
290                 }
291             } else {
292                 leadCC=trailCC;
293             }
294             append(c, leadCC, errorCode);
295         }
296     }
297     return TRUE;
298 }
299 
appendZeroCC(UChar32 c,UErrorCode & errorCode)300 UBool ReorderingBuffer::appendZeroCC(UChar32 c, UErrorCode &errorCode) {
301     int32_t cpLength=U16_LENGTH(c);
302     if(remainingCapacity<cpLength && !resize(cpLength, errorCode)) {
303         return FALSE;
304     }
305     remainingCapacity-=cpLength;
306     if(cpLength==1) {
307         *limit++=(UChar)c;
308     } else {
309         limit[0]=U16_LEAD(c);
310         limit[1]=U16_TRAIL(c);
311         limit+=2;
312     }
313     lastCC=0;
314     reorderStart=limit;
315     return TRUE;
316 }
317 
appendZeroCC(const UChar * s,const UChar * sLimit,UErrorCode & errorCode)318 UBool ReorderingBuffer::appendZeroCC(const UChar *s, const UChar *sLimit, UErrorCode &errorCode) {
319     if(s==sLimit) {
320         return TRUE;
321     }
322     int32_t length=(int32_t)(sLimit-s);
323     if(remainingCapacity<length && !resize(length, errorCode)) {
324         return FALSE;
325     }
326     u_memcpy(limit, s, length);
327     limit+=length;
328     remainingCapacity-=length;
329     lastCC=0;
330     reorderStart=limit;
331     return TRUE;
332 }
333 
remove()334 void ReorderingBuffer::remove() {
335     reorderStart=limit=start;
336     remainingCapacity=str.getCapacity();
337     lastCC=0;
338 }
339 
removeSuffix(int32_t suffixLength)340 void ReorderingBuffer::removeSuffix(int32_t suffixLength) {
341     if(suffixLength<(limit-start)) {
342         limit-=suffixLength;
343         remainingCapacity+=suffixLength;
344     } else {
345         limit=start;
346         remainingCapacity=str.getCapacity();
347     }
348     lastCC=0;
349     reorderStart=limit;
350 }
351 
resize(int32_t appendLength,UErrorCode & errorCode)352 UBool ReorderingBuffer::resize(int32_t appendLength, UErrorCode &errorCode) {
353     int32_t reorderStartIndex=(int32_t)(reorderStart-start);
354     int32_t length=(int32_t)(limit-start);
355     str.releaseBuffer(length);
356     int32_t newCapacity=length+appendLength;
357     int32_t doubleCapacity=2*str.getCapacity();
358     if(newCapacity<doubleCapacity) {
359         newCapacity=doubleCapacity;
360     }
361     if(newCapacity<256) {
362         newCapacity=256;
363     }
364     start=str.getBuffer(newCapacity);
365     if(start==NULL) {
366         // getBuffer() already did str.setToBogus()
367         errorCode=U_MEMORY_ALLOCATION_ERROR;
368         return FALSE;
369     }
370     reorderStart=start+reorderStartIndex;
371     limit=start+length;
372     remainingCapacity=str.getCapacity()-length;
373     return TRUE;
374 }
375 
skipPrevious()376 void ReorderingBuffer::skipPrevious() {
377     codePointLimit=codePointStart;
378     UChar c=*--codePointStart;
379     if(U16_IS_TRAIL(c) && start<codePointStart && U16_IS_LEAD(*(codePointStart-1))) {
380         --codePointStart;
381     }
382 }
383 
previousCC()384 uint8_t ReorderingBuffer::previousCC() {
385     codePointLimit=codePointStart;
386     if(reorderStart>=codePointStart) {
387         return 0;
388     }
389     UChar32 c=*--codePointStart;
390     UChar c2;
391     if(U16_IS_TRAIL(c) && start<codePointStart && U16_IS_LEAD(c2=*(codePointStart-1))) {
392         --codePointStart;
393         c=U16_GET_SUPPLEMENTARY(c2, c);
394     }
395     return impl.getCCFromYesOrMaybeCP(c);
396 }
397 
398 // Inserts c somewhere before the last character.
399 // Requires 0<cc<lastCC which implies reorderStart<limit.
insert(UChar32 c,uint8_t cc)400 void ReorderingBuffer::insert(UChar32 c, uint8_t cc) {
401     for(setIterator(), skipPrevious(); previousCC()>cc;) {}
402     // insert c at codePointLimit, after the character with prevCC<=cc
403     UChar *q=limit;
404     UChar *r=limit+=U16_LENGTH(c);
405     do {
406         *--r=*--q;
407     } while(codePointLimit!=q);
408     writeCodePoint(q, c);
409     if(cc<=1) {
410         reorderStart=r;
411     }
412 }
413 
414 // Normalizer2Impl --------------------------------------------------------- ***
415 
416 struct CanonIterData : public UMemory {
417     CanonIterData(UErrorCode &errorCode);
418     ~CanonIterData();
419     void addToStartSet(UChar32 origin, UChar32 decompLead, UErrorCode &errorCode);
420     UMutableCPTrie *mutableTrie;
421     UCPTrie *trie;
422     UVector canonStartSets;  // contains UnicodeSet *
423 };
424 
~Normalizer2Impl()425 Normalizer2Impl::~Normalizer2Impl() {
426     delete fCanonIterData;
427 }
428 
429 void
init(const int32_t * inIndexes,const UCPTrie * inTrie,const uint16_t * inExtraData,const uint8_t * inSmallFCD)430 Normalizer2Impl::init(const int32_t *inIndexes, const UCPTrie *inTrie,
431                       const uint16_t *inExtraData, const uint8_t *inSmallFCD) {
432     minDecompNoCP = static_cast<UChar>(inIndexes[IX_MIN_DECOMP_NO_CP]);
433     minCompNoMaybeCP = static_cast<UChar>(inIndexes[IX_MIN_COMP_NO_MAYBE_CP]);
434     minLcccCP = static_cast<UChar>(inIndexes[IX_MIN_LCCC_CP]);
435 
436     minYesNo = static_cast<uint16_t>(inIndexes[IX_MIN_YES_NO]);
437     minYesNoMappingsOnly = static_cast<uint16_t>(inIndexes[IX_MIN_YES_NO_MAPPINGS_ONLY]);
438     minNoNo = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO]);
439     minNoNoCompBoundaryBefore = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_COMP_BOUNDARY_BEFORE]);
440     minNoNoCompNoMaybeCC = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_COMP_NO_MAYBE_CC]);
441     minNoNoEmpty = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_EMPTY]);
442     limitNoNo = static_cast<uint16_t>(inIndexes[IX_LIMIT_NO_NO]);
443     minMaybeYes = static_cast<uint16_t>(inIndexes[IX_MIN_MAYBE_YES]);
444     U_ASSERT((minMaybeYes & 7) == 0);  // 8-aligned for noNoDelta bit fields
445     centerNoNoDelta = (minMaybeYes >> DELTA_SHIFT) - MAX_DELTA - 1;
446 
447     normTrie=inTrie;
448 
449     maybeYesCompositions=inExtraData;
450     extraData=maybeYesCompositions+((MIN_NORMAL_MAYBE_YES-minMaybeYes)>>OFFSET_SHIFT);
451 
452     smallFCD=inSmallFCD;
453 }
454 
455 U_CDECL_BEGIN
456 
457 static uint32_t U_CALLCONV
segmentStarterMapper(const void *,uint32_t value)458 segmentStarterMapper(const void * /*context*/, uint32_t value) {
459     return value&CANON_NOT_SEGMENT_STARTER;
460 }
461 
462 U_CDECL_END
463 
464 void
addLcccChars(UnicodeSet & set) const465 Normalizer2Impl::addLcccChars(UnicodeSet &set) const {
466     UChar32 start = 0, end;
467     uint32_t norm16;
468     while ((end = ucptrie_getRange(normTrie, start, UCPMAP_RANGE_FIXED_LEAD_SURROGATES, INERT,
469                                    nullptr, nullptr, &norm16)) >= 0) {
470         if (norm16 > Normalizer2Impl::MIN_NORMAL_MAYBE_YES &&
471                 norm16 != Normalizer2Impl::JAMO_VT) {
472             set.add(start, end);
473         } else if (minNoNoCompNoMaybeCC <= norm16 && norm16 < limitNoNo) {
474             uint16_t fcd16 = getFCD16(start);
475             if (fcd16 > 0xff) { set.add(start, end); }
476         }
477         start = end + 1;
478     }
479 }
480 
481 void
addPropertyStarts(const USetAdder * sa,UErrorCode &) const482 Normalizer2Impl::addPropertyStarts(const USetAdder *sa, UErrorCode & /*errorCode*/) const {
483     // Add the start code point of each same-value range of the trie.
484     UChar32 start = 0, end;
485     uint32_t value;
486     while ((end = ucptrie_getRange(normTrie, start, UCPMAP_RANGE_FIXED_LEAD_SURROGATES, INERT,
487                                    nullptr, nullptr, &value)) >= 0) {
488         sa->add(sa->set, start);
489         if (start != end && isAlgorithmicNoNo((uint16_t)value) &&
490                 (value & Normalizer2Impl::DELTA_TCCC_MASK) > Normalizer2Impl::DELTA_TCCC_1) {
491             // Range of code points with same-norm16-value algorithmic decompositions.
492             // They might have different non-zero FCD16 values.
493             uint16_t prevFCD16 = getFCD16(start);
494             while (++start <= end) {
495                 uint16_t fcd16 = getFCD16(start);
496                 if (fcd16 != prevFCD16) {
497                     sa->add(sa->set, start);
498                     prevFCD16 = fcd16;
499                 }
500             }
501         }
502         start = end + 1;
503     }
504 
505     /* add Hangul LV syllables and LV+1 because of skippables */
506     for(UChar c=Hangul::HANGUL_BASE; c<Hangul::HANGUL_LIMIT; c+=Hangul::JAMO_T_COUNT) {
507         sa->add(sa->set, c);
508         sa->add(sa->set, c+1);
509     }
510     sa->add(sa->set, Hangul::HANGUL_LIMIT); /* add Hangul+1 to continue with other properties */
511 }
512 
513 void
addCanonIterPropertyStarts(const USetAdder * sa,UErrorCode & errorCode) const514 Normalizer2Impl::addCanonIterPropertyStarts(const USetAdder *sa, UErrorCode &errorCode) const {
515     // Add the start code point of each same-value range of the canonical iterator data trie.
516     if (!ensureCanonIterData(errorCode)) { return; }
517     // Currently only used for the SEGMENT_STARTER property.
518     UChar32 start = 0, end;
519     uint32_t value;
520     while ((end = ucptrie_getRange(fCanonIterData->trie, start, UCPMAP_RANGE_NORMAL, 0,
521                                    segmentStarterMapper, nullptr, &value)) >= 0) {
522         sa->add(sa->set, start);
523         start = end + 1;
524     }
525 }
526 
527 const UChar *
copyLowPrefixFromNulTerminated(const UChar * src,UChar32 minNeedDataCP,ReorderingBuffer * buffer,UErrorCode & errorCode) const528 Normalizer2Impl::copyLowPrefixFromNulTerminated(const UChar *src,
529                                                 UChar32 minNeedDataCP,
530                                                 ReorderingBuffer *buffer,
531                                                 UErrorCode &errorCode) const {
532     // Make some effort to support NUL-terminated strings reasonably.
533     // Take the part of the fast quick check loop that does not look up
534     // data and check the first part of the string.
535     // After this prefix, determine the string length to simplify the rest
536     // of the code.
537     const UChar *prevSrc=src;
538     UChar c;
539     while((c=*src++)<minNeedDataCP && c!=0) {}
540     // Back out the last character for full processing.
541     // Copy this prefix.
542     if(--src!=prevSrc) {
543         if(buffer!=NULL) {
544             buffer->appendZeroCC(prevSrc, src, errorCode);
545         }
546     }
547     return src;
548 }
549 
550 UnicodeString &
decompose(const UnicodeString & src,UnicodeString & dest,UErrorCode & errorCode) const551 Normalizer2Impl::decompose(const UnicodeString &src, UnicodeString &dest,
552                            UErrorCode &errorCode) const {
553     if(U_FAILURE(errorCode)) {
554         dest.setToBogus();
555         return dest;
556     }
557     const UChar *sArray=src.getBuffer();
558     if(&dest==&src || sArray==NULL) {
559         errorCode=U_ILLEGAL_ARGUMENT_ERROR;
560         dest.setToBogus();
561         return dest;
562     }
563     decompose(sArray, sArray+src.length(), dest, src.length(), errorCode);
564     return dest;
565 }
566 
567 void
decompose(const UChar * src,const UChar * limit,UnicodeString & dest,int32_t destLengthEstimate,UErrorCode & errorCode) const568 Normalizer2Impl::decompose(const UChar *src, const UChar *limit,
569                            UnicodeString &dest,
570                            int32_t destLengthEstimate,
571                            UErrorCode &errorCode) const {
572     if(destLengthEstimate<0 && limit!=NULL) {
573         destLengthEstimate=(int32_t)(limit-src);
574     }
575     dest.remove();
576     ReorderingBuffer buffer(*this, dest);
577     if(buffer.init(destLengthEstimate, errorCode)) {
578         decompose(src, limit, &buffer, errorCode);
579     }
580 }
581 
582 // Dual functionality:
583 // buffer!=NULL: normalize
584 // buffer==NULL: isNormalized/spanQuickCheckYes
585 const UChar *
decompose(const UChar * src,const UChar * limit,ReorderingBuffer * buffer,UErrorCode & errorCode) const586 Normalizer2Impl::decompose(const UChar *src, const UChar *limit,
587                            ReorderingBuffer *buffer,
588                            UErrorCode &errorCode) const {
589     UChar32 minNoCP=minDecompNoCP;
590     if(limit==NULL) {
591         src=copyLowPrefixFromNulTerminated(src, minNoCP, buffer, errorCode);
592         if(U_FAILURE(errorCode)) {
593             return src;
594         }
595         limit=u_strchr(src, 0);
596     }
597 
598     const UChar *prevSrc;
599     UChar32 c=0;
600     uint16_t norm16=0;
601 
602     // only for quick check
603     const UChar *prevBoundary=src;
604     uint8_t prevCC=0;
605 
606     for(;;) {
607         // count code units below the minimum or with irrelevant data for the quick check
608         for(prevSrc=src; src!=limit;) {
609             if( (c=*src)<minNoCP ||
610                 isMostDecompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c))
611             ) {
612                 ++src;
613             } else if(!U16_IS_LEAD(c)) {
614                 break;
615             } else {
616                 UChar c2;
617                 if((src+1)!=limit && U16_IS_TRAIL(c2=src[1])) {
618                     c=U16_GET_SUPPLEMENTARY(c, c2);
619                     norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c);
620                     if(isMostDecompYesAndZeroCC(norm16)) {
621                         src+=2;
622                     } else {
623                         break;
624                     }
625                 } else {
626                     ++src;  // unpaired lead surrogate: inert
627                 }
628             }
629         }
630         // copy these code units all at once
631         if(src!=prevSrc) {
632             if(buffer!=NULL) {
633                 if(!buffer->appendZeroCC(prevSrc, src, errorCode)) {
634                     break;
635                 }
636             } else {
637                 prevCC=0;
638                 prevBoundary=src;
639             }
640         }
641         if(src==limit) {
642             break;
643         }
644 
645         // Check one above-minimum, relevant code point.
646         src+=U16_LENGTH(c);
647         if(buffer!=NULL) {
648             if(!decompose(c, norm16, *buffer, errorCode)) {
649                 break;
650             }
651         } else {
652             if(isDecompYes(norm16)) {
653                 uint8_t cc=getCCFromYesOrMaybe(norm16);
654                 if(prevCC<=cc || cc==0) {
655                     prevCC=cc;
656                     if(cc<=1) {
657                         prevBoundary=src;
658                     }
659                     continue;
660                 }
661             }
662             return prevBoundary;  // "no" or cc out of order
663         }
664     }
665     return src;
666 }
667 
668 // Decompose a short piece of text which is likely to contain characters that
669 // fail the quick check loop and/or where the quick check loop's overhead
670 // is unlikely to be amortized.
671 // Called by the compose() and makeFCD() implementations.
672 const UChar *
decomposeShort(const UChar * src,const UChar * limit,UBool stopAtCompBoundary,UBool onlyContiguous,ReorderingBuffer & buffer,UErrorCode & errorCode) const673 Normalizer2Impl::decomposeShort(const UChar *src, const UChar *limit,
674                                 UBool stopAtCompBoundary, UBool onlyContiguous,
675                                 ReorderingBuffer &buffer, UErrorCode &errorCode) const {
676     if (U_FAILURE(errorCode)) {
677         return nullptr;
678     }
679     while(src<limit) {
680         if (stopAtCompBoundary && *src < minCompNoMaybeCP) {
681             return src;
682         }
683         const UChar *prevSrc = src;
684         UChar32 c;
685         uint16_t norm16;
686         UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, src, limit, c, norm16);
687         if (stopAtCompBoundary && norm16HasCompBoundaryBefore(norm16)) {
688             return prevSrc;
689         }
690         if(!decompose(c, norm16, buffer, errorCode)) {
691             return nullptr;
692         }
693         if (stopAtCompBoundary && norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
694             return src;
695         }
696     }
697     return src;
698 }
699 
decompose(UChar32 c,uint16_t norm16,ReorderingBuffer & buffer,UErrorCode & errorCode) const700 UBool Normalizer2Impl::decompose(UChar32 c, uint16_t norm16,
701                                  ReorderingBuffer &buffer,
702                                  UErrorCode &errorCode) const {
703     // get the decomposition and the lead and trail cc's
704     if (norm16 >= limitNoNo) {
705         if (isMaybeOrNonZeroCC(norm16)) {
706             return buffer.append(c, getCCFromYesOrMaybe(norm16), errorCode);
707         }
708         // Maps to an isCompYesAndZeroCC.
709         c=mapAlgorithmic(c, norm16);
710         norm16=getRawNorm16(c);
711     }
712     if (norm16 < minYesNo) {
713         // c does not decompose
714         return buffer.append(c, 0, errorCode);
715     } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
716         // Hangul syllable: decompose algorithmically
717         UChar jamos[3];
718         return buffer.appendZeroCC(jamos, jamos+Hangul::decompose(c, jamos), errorCode);
719     }
720     // c decomposes, get everything from the variable-length extra data
721     const uint16_t *mapping=getMapping(norm16);
722     uint16_t firstUnit=*mapping;
723     int32_t length=firstUnit&MAPPING_LENGTH_MASK;
724     uint8_t leadCC, trailCC;
725     trailCC=(uint8_t)(firstUnit>>8);
726     if(firstUnit&MAPPING_HAS_CCC_LCCC_WORD) {
727         leadCC=(uint8_t)(*(mapping-1)>>8);
728     } else {
729         leadCC=0;
730     }
731     return buffer.append((const UChar *)mapping+1, length, TRUE, leadCC, trailCC, errorCode);
732 }
733 
734 // Dual functionality:
735 // sink != nullptr: normalize
736 // sink == nullptr: isNormalized/spanQuickCheckYes
737 const uint8_t *
decomposeUTF8(uint32_t options,const uint8_t * src,const uint8_t * limit,ByteSink * sink,Edits * edits,UErrorCode & errorCode) const738 Normalizer2Impl::decomposeUTF8(uint32_t options,
739                                const uint8_t *src, const uint8_t *limit,
740                                ByteSink *sink, Edits *edits, UErrorCode &errorCode) const {
741     U_ASSERT(limit != nullptr);
742     UnicodeString s16;
743     uint8_t minNoLead = leadByteForCP(minDecompNoCP);
744 
745     const uint8_t *prevBoundary = src;
746     // only for quick check
747     uint8_t prevCC = 0;
748 
749     for (;;) {
750         // Fast path: Scan over a sequence of characters below the minimum "no" code point,
751         // or with (decompYes && ccc==0) properties.
752         const uint8_t *fastStart = src;
753         const uint8_t *prevSrc;
754         uint16_t norm16 = 0;
755 
756         for (;;) {
757             if (src == limit) {
758                 if (prevBoundary != limit && sink != nullptr) {
759                     ByteSinkUtil::appendUnchanged(prevBoundary, limit,
760                                                   *sink, options, edits, errorCode);
761                 }
762                 return src;
763             }
764             if (*src < minNoLead) {
765                 ++src;
766             } else {
767                 prevSrc = src;
768                 UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16);
769                 if (!isMostDecompYesAndZeroCC(norm16)) {
770                     break;
771                 }
772             }
773         }
774         // isMostDecompYesAndZeroCC(norm16) is false, that is, norm16>=minYesNo,
775         // and the current character at [prevSrc..src[ is not a common case with cc=0
776         // (MIN_NORMAL_MAYBE_YES or JAMO_VT).
777         // It could still be a maybeYes with cc=0.
778         if (prevSrc != fastStart) {
779             // The fast path looped over yes/0 characters before the current one.
780             if (sink != nullptr &&
781                     !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
782                                                    *sink, options, edits, errorCode)) {
783                 break;
784             }
785             prevBoundary = prevSrc;
786             prevCC = 0;
787         }
788 
789         // Medium-fast path: Quick check.
790         if (isMaybeOrNonZeroCC(norm16)) {
791             // Does not decompose.
792             uint8_t cc = getCCFromYesOrMaybe(norm16);
793             if (prevCC <= cc || cc == 0) {
794                 prevCC = cc;
795                 if (cc <= 1) {
796                     if (sink != nullptr &&
797                             !ByteSinkUtil::appendUnchanged(prevBoundary, src,
798                                                            *sink, options, edits, errorCode)) {
799                         break;
800                     }
801                     prevBoundary = src;
802                 }
803                 continue;
804             }
805         }
806         if (sink == nullptr) {
807             return prevBoundary;  // quick check: "no" or cc out of order
808         }
809 
810         // Slow path
811         // Decompose up to and including the current character.
812         if (prevBoundary != prevSrc && norm16HasDecompBoundaryBefore(norm16)) {
813             if (!ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
814                                                *sink, options, edits, errorCode)) {
815                 break;
816             }
817             prevBoundary = prevSrc;
818         }
819         ReorderingBuffer buffer(*this, s16, errorCode);
820         if (U_FAILURE(errorCode)) {
821             break;
822         }
823         decomposeShort(prevBoundary, src, STOP_AT_LIMIT, FALSE /* onlyContiguous */,
824                        buffer, errorCode);
825         // Decompose until the next boundary.
826         if (buffer.getLastCC() > 1) {
827             src = decomposeShort(src, limit, STOP_AT_DECOMP_BOUNDARY, FALSE /* onlyContiguous */,
828                                  buffer, errorCode);
829         }
830         if (U_FAILURE(errorCode)) {
831             break;
832         }
833         if ((src - prevSrc) > INT32_MAX) {  // guard before buffer.equals()
834             errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
835             break;
836         }
837         // We already know there was a change if the original character decomposed;
838         // otherwise compare.
839         if (isMaybeOrNonZeroCC(norm16) && buffer.equals(prevBoundary, src)) {
840             if (!ByteSinkUtil::appendUnchanged(prevBoundary, src,
841                                                *sink, options, edits, errorCode)) {
842                 break;
843             }
844         } else {
845             if (!ByteSinkUtil::appendChange(prevBoundary, src, buffer.getStart(), buffer.length(),
846                                             *sink, edits, errorCode)) {
847                 break;
848             }
849         }
850         prevBoundary = src;
851         prevCC = 0;
852     }
853     return src;
854 }
855 
856 const uint8_t *
decomposeShort(const uint8_t * src,const uint8_t * limit,StopAt stopAt,UBool onlyContiguous,ReorderingBuffer & buffer,UErrorCode & errorCode) const857 Normalizer2Impl::decomposeShort(const uint8_t *src, const uint8_t *limit,
858                                 StopAt stopAt, UBool onlyContiguous,
859                                 ReorderingBuffer &buffer, UErrorCode &errorCode) const {
860     if (U_FAILURE(errorCode)) {
861         return nullptr;
862     }
863     while (src < limit) {
864         const uint8_t *prevSrc = src;
865         uint16_t norm16;
866         UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16);
867         // Get the decomposition and the lead and trail cc's.
868         UChar32 c = U_SENTINEL;
869         if (norm16 >= limitNoNo) {
870             if (isMaybeOrNonZeroCC(norm16)) {
871                 // No comp boundaries around this character.
872                 uint8_t cc = getCCFromYesOrMaybe(norm16);
873                 if (cc == 0 && stopAt == STOP_AT_DECOMP_BOUNDARY) {
874                     return prevSrc;
875                 }
876                 c = codePointFromValidUTF8(prevSrc, src);
877                 if (!buffer.append(c, cc, errorCode)) {
878                     return nullptr;
879                 }
880                 if (stopAt == STOP_AT_DECOMP_BOUNDARY && buffer.getLastCC() <= 1) {
881                     return src;
882                 }
883                 continue;
884             }
885             // Maps to an isCompYesAndZeroCC.
886             if (stopAt != STOP_AT_LIMIT) {
887                 return prevSrc;
888             }
889             c = codePointFromValidUTF8(prevSrc, src);
890             c = mapAlgorithmic(c, norm16);
891             norm16 = getRawNorm16(c);
892         } else if (stopAt != STOP_AT_LIMIT && norm16 < minNoNoCompNoMaybeCC) {
893             return prevSrc;
894         }
895         // norm16!=INERT guarantees that [prevSrc, src[ is valid UTF-8.
896         // We do not see invalid UTF-8 here because
897         // its norm16==INERT is normalization-inert,
898         // so it gets copied unchanged in the fast path,
899         // and we stop the slow path where invalid UTF-8 begins.
900         // c >= 0 is the result of an algorithmic mapping.
901         U_ASSERT(c >= 0 || norm16 != INERT);
902         if (norm16 < minYesNo) {
903             if (c < 0) {
904                 c = codePointFromValidUTF8(prevSrc, src);
905             }
906             // does not decompose
907             if (!buffer.append(c, 0, errorCode)) {
908                 return nullptr;
909             }
910         } else if (isHangulLV(norm16) || isHangulLVT(norm16)) {
911             // Hangul syllable: decompose algorithmically
912             if (c < 0) {
913                 c = codePointFromValidUTF8(prevSrc, src);
914             }
915             char16_t jamos[3];
916             if (!buffer.appendZeroCC(jamos, jamos+Hangul::decompose(c, jamos), errorCode)) {
917                 return nullptr;
918             }
919         } else {
920             // The character decomposes, get everything from the variable-length extra data.
921             const uint16_t *mapping = getMapping(norm16);
922             uint16_t firstUnit = *mapping;
923             int32_t length = firstUnit & MAPPING_LENGTH_MASK;
924             uint8_t trailCC = (uint8_t)(firstUnit >> 8);
925             uint8_t leadCC;
926             if (firstUnit & MAPPING_HAS_CCC_LCCC_WORD) {
927                 leadCC = (uint8_t)(*(mapping-1) >> 8);
928             } else {
929                 leadCC = 0;
930             }
931             if (leadCC == 0 && stopAt == STOP_AT_DECOMP_BOUNDARY) {
932                 return prevSrc;
933             }
934             if (!buffer.append((const char16_t *)mapping+1, length, TRUE, leadCC, trailCC, errorCode)) {
935                 return nullptr;
936             }
937         }
938         if ((stopAt == STOP_AT_COMP_BOUNDARY && norm16HasCompBoundaryAfter(norm16, onlyContiguous)) ||
939                 (stopAt == STOP_AT_DECOMP_BOUNDARY && buffer.getLastCC() <= 1)) {
940             return src;
941         }
942     }
943     return src;
944 }
945 
946 const UChar *
getDecomposition(UChar32 c,UChar buffer[4],int32_t & length) const947 Normalizer2Impl::getDecomposition(UChar32 c, UChar buffer[4], int32_t &length) const {
948     uint16_t norm16;
949     if(c<minDecompNoCP || isMaybeOrNonZeroCC(norm16=getNorm16(c))) {
950         // c does not decompose
951         return nullptr;
952     }
953     const UChar *decomp = nullptr;
954     if(isDecompNoAlgorithmic(norm16)) {
955         // Maps to an isCompYesAndZeroCC.
956         c=mapAlgorithmic(c, norm16);
957         decomp=buffer;
958         length=0;
959         U16_APPEND_UNSAFE(buffer, length, c);
960         // The mapping might decompose further.
961         norm16 = getRawNorm16(c);
962     }
963     if (norm16 < minYesNo) {
964         return decomp;
965     } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
966         // Hangul syllable: decompose algorithmically
967         length=Hangul::decompose(c, buffer);
968         return buffer;
969     }
970     // c decomposes, get everything from the variable-length extra data
971     const uint16_t *mapping=getMapping(norm16);
972     length=*mapping&MAPPING_LENGTH_MASK;
973     return (const UChar *)mapping+1;
974 }
975 
976 // The capacity of the buffer must be 30=MAPPING_LENGTH_MASK-1
977 // so that a raw mapping fits that consists of one unit ("rm0")
978 // plus all but the first two code units of the normal mapping.
979 // The maximum length of a normal mapping is 31=MAPPING_LENGTH_MASK.
980 const UChar *
getRawDecomposition(UChar32 c,UChar buffer[30],int32_t & length) const981 Normalizer2Impl::getRawDecomposition(UChar32 c, UChar buffer[30], int32_t &length) const {
982     uint16_t norm16;
983     if(c<minDecompNoCP || isDecompYes(norm16=getNorm16(c))) {
984         // c does not decompose
985         return NULL;
986     } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
987         // Hangul syllable: decompose algorithmically
988         Hangul::getRawDecomposition(c, buffer);
989         length=2;
990         return buffer;
991     } else if(isDecompNoAlgorithmic(norm16)) {
992         c=mapAlgorithmic(c, norm16);
993         length=0;
994         U16_APPEND_UNSAFE(buffer, length, c);
995         return buffer;
996     }
997     // c decomposes, get everything from the variable-length extra data
998     const uint16_t *mapping=getMapping(norm16);
999     uint16_t firstUnit=*mapping;
1000     int32_t mLength=firstUnit&MAPPING_LENGTH_MASK;  // length of normal mapping
1001     if(firstUnit&MAPPING_HAS_RAW_MAPPING) {
1002         // Read the raw mapping from before the firstUnit and before the optional ccc/lccc word.
1003         // Bit 7=MAPPING_HAS_CCC_LCCC_WORD
1004         const uint16_t *rawMapping=mapping-((firstUnit>>7)&1)-1;
1005         uint16_t rm0=*rawMapping;
1006         if(rm0<=MAPPING_LENGTH_MASK) {
1007             length=rm0;
1008             return (const UChar *)rawMapping-rm0;
1009         } else {
1010             // Copy the normal mapping and replace its first two code units with rm0.
1011             buffer[0]=(UChar)rm0;
1012             u_memcpy(buffer+1, (const UChar *)mapping+1+2, mLength-2);
1013             length=mLength-1;
1014             return buffer;
1015         }
1016     } else {
1017         length=mLength;
1018         return (const UChar *)mapping+1;
1019     }
1020 }
1021 
decomposeAndAppend(const UChar * src,const UChar * limit,UBool doDecompose,UnicodeString & safeMiddle,ReorderingBuffer & buffer,UErrorCode & errorCode) const1022 void Normalizer2Impl::decomposeAndAppend(const UChar *src, const UChar *limit,
1023                                          UBool doDecompose,
1024                                          UnicodeString &safeMiddle,
1025                                          ReorderingBuffer &buffer,
1026                                          UErrorCode &errorCode) const {
1027     buffer.copyReorderableSuffixTo(safeMiddle);
1028     if(doDecompose) {
1029         decompose(src, limit, &buffer, errorCode);
1030         return;
1031     }
1032     // Just merge the strings at the boundary.
1033     bool isFirst = true;
1034     uint8_t firstCC = 0, prevCC = 0, cc;
1035     const UChar *p = src;
1036     while (p != limit) {
1037         const UChar *codePointStart = p;
1038         UChar32 c;
1039         uint16_t norm16;
1040         UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16);
1041         if ((cc = getCC(norm16)) == 0) {
1042             p = codePointStart;
1043             break;
1044         }
1045         if (isFirst) {
1046             firstCC = cc;
1047             isFirst = false;
1048         }
1049         prevCC = cc;
1050     }
1051     if(limit==NULL) {  // appendZeroCC() needs limit!=NULL
1052         limit=u_strchr(p, 0);
1053     }
1054 
1055     if (buffer.append(src, (int32_t)(p - src), FALSE, firstCC, prevCC, errorCode)) {
1056         buffer.appendZeroCC(p, limit, errorCode);
1057     }
1058 }
1059 
hasDecompBoundaryBefore(UChar32 c) const1060 UBool Normalizer2Impl::hasDecompBoundaryBefore(UChar32 c) const {
1061     return c < minLcccCP || (c <= 0xffff && !singleLeadMightHaveNonZeroFCD16(c)) ||
1062         norm16HasDecompBoundaryBefore(getNorm16(c));
1063 }
1064 
norm16HasDecompBoundaryBefore(uint16_t norm16) const1065 UBool Normalizer2Impl::norm16HasDecompBoundaryBefore(uint16_t norm16) const {
1066     if (norm16 < minNoNoCompNoMaybeCC) {
1067         return TRUE;
1068     }
1069     if (norm16 >= limitNoNo) {
1070         return norm16 <= MIN_NORMAL_MAYBE_YES || norm16 == JAMO_VT;
1071     }
1072     // c decomposes, get everything from the variable-length extra data
1073     const uint16_t *mapping=getMapping(norm16);
1074     uint16_t firstUnit=*mapping;
1075     // TRUE if leadCC==0 (hasFCDBoundaryBefore())
1076     return (firstUnit&MAPPING_HAS_CCC_LCCC_WORD)==0 || (*(mapping-1)&0xff00)==0;
1077 }
1078 
hasDecompBoundaryAfter(UChar32 c) const1079 UBool Normalizer2Impl::hasDecompBoundaryAfter(UChar32 c) const {
1080     if (c < minDecompNoCP) {
1081         return TRUE;
1082     }
1083     if (c <= 0xffff && !singleLeadMightHaveNonZeroFCD16(c)) {
1084         return TRUE;
1085     }
1086     return norm16HasDecompBoundaryAfter(getNorm16(c));
1087 }
1088 
norm16HasDecompBoundaryAfter(uint16_t norm16) const1089 UBool Normalizer2Impl::norm16HasDecompBoundaryAfter(uint16_t norm16) const {
1090     if(norm16 <= minYesNo || isHangulLVT(norm16)) {
1091         return TRUE;
1092     }
1093     if (norm16 >= limitNoNo) {
1094         if (isMaybeOrNonZeroCC(norm16)) {
1095             return norm16 <= MIN_NORMAL_MAYBE_YES || norm16 == JAMO_VT;
1096         }
1097         // Maps to an isCompYesAndZeroCC.
1098         return (norm16 & DELTA_TCCC_MASK) <= DELTA_TCCC_1;
1099     }
1100     // c decomposes, get everything from the variable-length extra data
1101     const uint16_t *mapping=getMapping(norm16);
1102     uint16_t firstUnit=*mapping;
1103     // decomp after-boundary: same as hasFCDBoundaryAfter(),
1104     // fcd16<=1 || trailCC==0
1105     if(firstUnit>0x1ff) {
1106         return FALSE;  // trailCC>1
1107     }
1108     if(firstUnit<=0xff) {
1109         return TRUE;  // trailCC==0
1110     }
1111     // if(trailCC==1) test leadCC==0, same as checking for before-boundary
1112     // TRUE if leadCC==0 (hasFCDBoundaryBefore())
1113     return (firstUnit&MAPPING_HAS_CCC_LCCC_WORD)==0 || (*(mapping-1)&0xff00)==0;
1114 }
1115 
1116 /*
1117  * Finds the recomposition result for
1118  * a forward-combining "lead" character,
1119  * specified with a pointer to its compositions list,
1120  * and a backward-combining "trail" character.
1121  *
1122  * If the lead and trail characters combine, then this function returns
1123  * the following "compositeAndFwd" value:
1124  * Bits 21..1  composite character
1125  * Bit      0  set if the composite is a forward-combining starter
1126  * otherwise it returns -1.
1127  *
1128  * The compositions list has (trail, compositeAndFwd) pair entries,
1129  * encoded as either pairs or triples of 16-bit units.
1130  * The last entry has the high bit of its first unit set.
1131  *
1132  * The list is sorted by ascending trail characters (there are no duplicates).
1133  * A linear search is used.
1134  *
1135  * See normalizer2impl.h for a more detailed description
1136  * of the compositions list format.
1137  */
combine(const uint16_t * list,UChar32 trail)1138 int32_t Normalizer2Impl::combine(const uint16_t *list, UChar32 trail) {
1139     uint16_t key1, firstUnit;
1140     if(trail<COMP_1_TRAIL_LIMIT) {
1141         // trail character is 0..33FF
1142         // result entry may have 2 or 3 units
1143         key1=(uint16_t)(trail<<1);
1144         while(key1>(firstUnit=*list)) {
1145             list+=2+(firstUnit&COMP_1_TRIPLE);
1146         }
1147         if(key1==(firstUnit&COMP_1_TRAIL_MASK)) {
1148             if(firstUnit&COMP_1_TRIPLE) {
1149                 return ((int32_t)list[1]<<16)|list[2];
1150             } else {
1151                 return list[1];
1152             }
1153         }
1154     } else {
1155         // trail character is 3400..10FFFF
1156         // result entry has 3 units
1157         key1=(uint16_t)(COMP_1_TRAIL_LIMIT+
1158                         (((trail>>COMP_1_TRAIL_SHIFT))&
1159                           ~COMP_1_TRIPLE));
1160         uint16_t key2=(uint16_t)(trail<<COMP_2_TRAIL_SHIFT);
1161         uint16_t secondUnit;
1162         for(;;) {
1163             if(key1>(firstUnit=*list)) {
1164                 list+=2+(firstUnit&COMP_1_TRIPLE);
1165             } else if(key1==(firstUnit&COMP_1_TRAIL_MASK)) {
1166                 if(key2>(secondUnit=list[1])) {
1167                     if(firstUnit&COMP_1_LAST_TUPLE) {
1168                         break;
1169                     } else {
1170                         list+=3;
1171                     }
1172                 } else if(key2==(secondUnit&COMP_2_TRAIL_MASK)) {
1173                     return ((int32_t)(secondUnit&~COMP_2_TRAIL_MASK)<<16)|list[2];
1174                 } else {
1175                     break;
1176                 }
1177             } else {
1178                 break;
1179             }
1180         }
1181     }
1182     return -1;
1183 }
1184 
1185 /**
1186   * @param list some character's compositions list
1187   * @param set recursively receives the composites from these compositions
1188   */
addComposites(const uint16_t * list,UnicodeSet & set) const1189 void Normalizer2Impl::addComposites(const uint16_t *list, UnicodeSet &set) const {
1190     uint16_t firstUnit;
1191     int32_t compositeAndFwd;
1192     do {
1193         firstUnit=*list;
1194         if((firstUnit&COMP_1_TRIPLE)==0) {
1195             compositeAndFwd=list[1];
1196             list+=2;
1197         } else {
1198             compositeAndFwd=(((int32_t)list[1]&~COMP_2_TRAIL_MASK)<<16)|list[2];
1199             list+=3;
1200         }
1201         UChar32 composite=compositeAndFwd>>1;
1202         if((compositeAndFwd&1)!=0) {
1203             addComposites(getCompositionsListForComposite(getRawNorm16(composite)), set);
1204         }
1205         set.add(composite);
1206     } while((firstUnit&COMP_1_LAST_TUPLE)==0);
1207 }
1208 
1209 /*
1210  * Recomposes the buffer text starting at recomposeStartIndex
1211  * (which is in NFD - decomposed and canonically ordered),
1212  * and truncates the buffer contents.
1213  *
1214  * Note that recomposition never lengthens the text:
1215  * Any character consists of either one or two code units;
1216  * a composition may contain at most one more code unit than the original starter,
1217  * while the combining mark that is removed has at least one code unit.
1218  */
recompose(ReorderingBuffer & buffer,int32_t recomposeStartIndex,UBool onlyContiguous) const1219 void Normalizer2Impl::recompose(ReorderingBuffer &buffer, int32_t recomposeStartIndex,
1220                                 UBool onlyContiguous) const {
1221     UChar *p=buffer.getStart()+recomposeStartIndex;
1222     UChar *limit=buffer.getLimit();
1223     if(p==limit) {
1224         return;
1225     }
1226 
1227     UChar *starter, *pRemove, *q, *r;
1228     const uint16_t *compositionsList;
1229     UChar32 c, compositeAndFwd;
1230     uint16_t norm16;
1231     uint8_t cc, prevCC;
1232     UBool starterIsSupplementary;
1233 
1234     // Some of the following variables are not used until we have a forward-combining starter
1235     // and are only initialized now to avoid compiler warnings.
1236     compositionsList=NULL;  // used as indicator for whether we have a forward-combining starter
1237     starter=NULL;
1238     starterIsSupplementary=FALSE;
1239     prevCC=0;
1240 
1241     for(;;) {
1242         UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16);
1243         cc=getCCFromYesOrMaybe(norm16);
1244         if( // this character combines backward and
1245             isMaybe(norm16) &&
1246             // we have seen a starter that combines forward and
1247             compositionsList!=NULL &&
1248             // the backward-combining character is not blocked
1249             (prevCC<cc || prevCC==0)
1250         ) {
1251             if(isJamoVT(norm16)) {
1252                 // c is a Jamo V/T, see if we can compose it with the previous character.
1253                 if(c<Hangul::JAMO_T_BASE) {
1254                     // c is a Jamo Vowel, compose with previous Jamo L and following Jamo T.
1255                     UChar prev=(UChar)(*starter-Hangul::JAMO_L_BASE);
1256                     if(prev<Hangul::JAMO_L_COUNT) {
1257                         pRemove=p-1;
1258                         UChar syllable=(UChar)
1259                             (Hangul::HANGUL_BASE+
1260                              (prev*Hangul::JAMO_V_COUNT+(c-Hangul::JAMO_V_BASE))*
1261                              Hangul::JAMO_T_COUNT);
1262                         UChar t;
1263                         if(p!=limit && (t=(UChar)(*p-Hangul::JAMO_T_BASE))<Hangul::JAMO_T_COUNT) {
1264                             ++p;
1265                             syllable+=t;  // The next character was a Jamo T.
1266                         }
1267                         *starter=syllable;
1268                         // remove the Jamo V/T
1269                         q=pRemove;
1270                         r=p;
1271                         while(r<limit) {
1272                             *q++=*r++;
1273                         }
1274                         limit=q;
1275                         p=pRemove;
1276                     }
1277                 }
1278                 /*
1279                  * No "else" for Jamo T:
1280                  * Since the input is in NFD, there are no Hangul LV syllables that
1281                  * a Jamo T could combine with.
1282                  * All Jamo Ts are combined above when handling Jamo Vs.
1283                  */
1284                 if(p==limit) {
1285                     break;
1286                 }
1287                 compositionsList=NULL;
1288                 continue;
1289             } else if((compositeAndFwd=combine(compositionsList, c))>=0) {
1290                 // The starter and the combining mark (c) do combine.
1291                 UChar32 composite=compositeAndFwd>>1;
1292 
1293                 // Replace the starter with the composite, remove the combining mark.
1294                 pRemove=p-U16_LENGTH(c);  // pRemove & p: start & limit of the combining mark
1295                 if(starterIsSupplementary) {
1296                     if(U_IS_SUPPLEMENTARY(composite)) {
1297                         // both are supplementary
1298                         starter[0]=U16_LEAD(composite);
1299                         starter[1]=U16_TRAIL(composite);
1300                     } else {
1301                         *starter=(UChar)composite;
1302                         // The composite is shorter than the starter,
1303                         // move the intermediate characters forward one.
1304                         starterIsSupplementary=FALSE;
1305                         q=starter+1;
1306                         r=q+1;
1307                         while(r<pRemove) {
1308                             *q++=*r++;
1309                         }
1310                         --pRemove;
1311                     }
1312                 } else if(U_IS_SUPPLEMENTARY(composite)) {
1313                     // The composite is longer than the starter,
1314                     // move the intermediate characters back one.
1315                     starterIsSupplementary=TRUE;
1316                     ++starter;  // temporarily increment for the loop boundary
1317                     q=pRemove;
1318                     r=++pRemove;
1319                     while(starter<q) {
1320                         *--r=*--q;
1321                     }
1322                     *starter=U16_TRAIL(composite);
1323                     *--starter=U16_LEAD(composite);  // undo the temporary increment
1324                 } else {
1325                     // both are on the BMP
1326                     *starter=(UChar)composite;
1327                 }
1328 
1329                 /* remove the combining mark by moving the following text over it */
1330                 if(pRemove<p) {
1331                     q=pRemove;
1332                     r=p;
1333                     while(r<limit) {
1334                         *q++=*r++;
1335                     }
1336                     limit=q;
1337                     p=pRemove;
1338                 }
1339                 // Keep prevCC because we removed the combining mark.
1340 
1341                 if(p==limit) {
1342                     break;
1343                 }
1344                 // Is the composite a starter that combines forward?
1345                 if(compositeAndFwd&1) {
1346                     compositionsList=
1347                         getCompositionsListForComposite(getRawNorm16(composite));
1348                 } else {
1349                     compositionsList=NULL;
1350                 }
1351 
1352                 // We combined; continue with looking for compositions.
1353                 continue;
1354             }
1355         }
1356 
1357         // no combination this time
1358         prevCC=cc;
1359         if(p==limit) {
1360             break;
1361         }
1362 
1363         // If c did not combine, then check if it is a starter.
1364         if(cc==0) {
1365             // Found a new starter.
1366             if((compositionsList=getCompositionsListForDecompYes(norm16))!=NULL) {
1367                 // It may combine with something, prepare for it.
1368                 if(U_IS_BMP(c)) {
1369                     starterIsSupplementary=FALSE;
1370                     starter=p-1;
1371                 } else {
1372                     starterIsSupplementary=TRUE;
1373                     starter=p-2;
1374                 }
1375             }
1376         } else if(onlyContiguous) {
1377             // FCC: no discontiguous compositions; any intervening character blocks.
1378             compositionsList=NULL;
1379         }
1380     }
1381     buffer.setReorderingLimit(limit);
1382 }
1383 
1384 UChar32
composePair(UChar32 a,UChar32 b) const1385 Normalizer2Impl::composePair(UChar32 a, UChar32 b) const {
1386     uint16_t norm16=getNorm16(a);  // maps an out-of-range 'a' to inert norm16
1387     const uint16_t *list;
1388     if(isInert(norm16)) {
1389         return U_SENTINEL;
1390     } else if(norm16<minYesNoMappingsOnly) {
1391         // a combines forward.
1392         if(isJamoL(norm16)) {
1393             b-=Hangul::JAMO_V_BASE;
1394             if(0<=b && b<Hangul::JAMO_V_COUNT) {
1395                 return
1396                     (Hangul::HANGUL_BASE+
1397                      ((a-Hangul::JAMO_L_BASE)*Hangul::JAMO_V_COUNT+b)*
1398                      Hangul::JAMO_T_COUNT);
1399             } else {
1400                 return U_SENTINEL;
1401             }
1402         } else if(isHangulLV(norm16)) {
1403             b-=Hangul::JAMO_T_BASE;
1404             if(0<b && b<Hangul::JAMO_T_COUNT) {  // not b==0!
1405                 return a+b;
1406             } else {
1407                 return U_SENTINEL;
1408             }
1409         } else {
1410             // 'a' has a compositions list in extraData
1411             list=getMapping(norm16);
1412             if(norm16>minYesNo) {  // composite 'a' has both mapping & compositions list
1413                 list+=  // mapping pointer
1414                     1+  // +1 to skip the first unit with the mapping length
1415                     (*list&MAPPING_LENGTH_MASK);  // + mapping length
1416             }
1417         }
1418     } else if(norm16<minMaybeYes || MIN_NORMAL_MAYBE_YES<=norm16) {
1419         return U_SENTINEL;
1420     } else {
1421         list=getCompositionsListForMaybe(norm16);
1422     }
1423     if(b<0 || 0x10ffff<b) {  // combine(list, b) requires a valid code point b
1424         return U_SENTINEL;
1425     }
1426 #if U_SIGNED_RIGHT_SHIFT_IS_ARITHMETIC
1427     return combine(list, b)>>1;
1428 #else
1429     int32_t compositeAndFwd=combine(list, b);
1430     return compositeAndFwd>=0 ? compositeAndFwd>>1 : U_SENTINEL;
1431 #endif
1432 }
1433 
1434 // Very similar to composeQuickCheck(): Make the same changes in both places if relevant.
1435 // doCompose: normalize
1436 // !doCompose: isNormalized (buffer must be empty and initialized)
1437 UBool
compose(const UChar * src,const UChar * limit,UBool onlyContiguous,UBool doCompose,ReorderingBuffer & buffer,UErrorCode & errorCode) const1438 Normalizer2Impl::compose(const UChar *src, const UChar *limit,
1439                          UBool onlyContiguous,
1440                          UBool doCompose,
1441                          ReorderingBuffer &buffer,
1442                          UErrorCode &errorCode) const {
1443     const UChar *prevBoundary=src;
1444     UChar32 minNoMaybeCP=minCompNoMaybeCP;
1445     if(limit==NULL) {
1446         src=copyLowPrefixFromNulTerminated(src, minNoMaybeCP,
1447                                            doCompose ? &buffer : NULL,
1448                                            errorCode);
1449         if(U_FAILURE(errorCode)) {
1450             return FALSE;
1451         }
1452         limit=u_strchr(src, 0);
1453         if (prevBoundary != src) {
1454             if (hasCompBoundaryAfter(*(src-1), onlyContiguous)) {
1455                 prevBoundary = src;
1456             } else {
1457                 buffer.removeSuffix(1);
1458                 prevBoundary = --src;
1459             }
1460         }
1461     }
1462 
1463     for (;;) {
1464         // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
1465         // or with (compYes && ccc==0) properties.
1466         const UChar *prevSrc;
1467         UChar32 c = 0;
1468         uint16_t norm16 = 0;
1469         for (;;) {
1470             if (src == limit) {
1471                 if (prevBoundary != limit && doCompose) {
1472                     buffer.appendZeroCC(prevBoundary, limit, errorCode);
1473                 }
1474                 return TRUE;
1475             }
1476             if( (c=*src)<minNoMaybeCP ||
1477                 isCompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c))
1478             ) {
1479                 ++src;
1480             } else {
1481                 prevSrc = src++;
1482                 if(!U16_IS_LEAD(c)) {
1483                     break;
1484                 } else {
1485                     UChar c2;
1486                     if(src!=limit && U16_IS_TRAIL(c2=*src)) {
1487                         ++src;
1488                         c=U16_GET_SUPPLEMENTARY(c, c2);
1489                         norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c);
1490                         if(!isCompYesAndZeroCC(norm16)) {
1491                             break;
1492                         }
1493                     }
1494                 }
1495             }
1496         }
1497         // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
1498         // The current character is either a "noNo" (has a mapping)
1499         // or a "maybeYes" (combines backward)
1500         // or a "yesYes" with ccc!=0.
1501         // It is not a Hangul syllable or Jamo L because those have "yes" properties.
1502 
1503         // Medium-fast path: Handle cases that do not require full decomposition and recomposition.
1504         if (!isMaybeOrNonZeroCC(norm16)) {  // minNoNo <= norm16 < minMaybeYes
1505             if (!doCompose) {
1506                 return FALSE;
1507             }
1508             // Fast path for mapping a character that is immediately surrounded by boundaries.
1509             // In this case, we need not decompose around the current character.
1510             if (isDecompNoAlgorithmic(norm16)) {
1511                 // Maps to a single isCompYesAndZeroCC character
1512                 // which also implies hasCompBoundaryBefore.
1513                 if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
1514                         hasCompBoundaryBefore(src, limit)) {
1515                     if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1516                         break;
1517                     }
1518                     if(!buffer.append(mapAlgorithmic(c, norm16), 0, errorCode)) {
1519                         break;
1520                     }
1521                     prevBoundary = src;
1522                     continue;
1523                 }
1524             } else if (norm16 < minNoNoCompBoundaryBefore) {
1525                 // The mapping is comp-normalized which also implies hasCompBoundaryBefore.
1526                 if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
1527                         hasCompBoundaryBefore(src, limit)) {
1528                     if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1529                         break;
1530                     }
1531                     const UChar *mapping = reinterpret_cast<const UChar *>(getMapping(norm16));
1532                     int32_t length = *mapping++ & MAPPING_LENGTH_MASK;
1533                     if(!buffer.appendZeroCC(mapping, mapping + length, errorCode)) {
1534                         break;
1535                     }
1536                     prevBoundary = src;
1537                     continue;
1538                 }
1539             } else if (norm16 >= minNoNoEmpty) {
1540                 // The current character maps to nothing.
1541                 // Simply omit it from the output if there is a boundary before _or_ after it.
1542                 // The character itself implies no boundaries.
1543                 if (hasCompBoundaryBefore(src, limit) ||
1544                         hasCompBoundaryAfter(prevBoundary, prevSrc, onlyContiguous)) {
1545                     if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1546                         break;
1547                     }
1548                     prevBoundary = src;
1549                     continue;
1550                 }
1551             }
1552             // Other "noNo" type, or need to examine more text around this character:
1553             // Fall through to the slow path.
1554         } else if (isJamoVT(norm16) && prevBoundary != prevSrc) {
1555             UChar prev=*(prevSrc-1);
1556             if(c<Hangul::JAMO_T_BASE) {
1557                 // The current character is a Jamo Vowel,
1558                 // compose with previous Jamo L and following Jamo T.
1559                 UChar l = (UChar)(prev-Hangul::JAMO_L_BASE);
1560                 if(l<Hangul::JAMO_L_COUNT) {
1561                     if (!doCompose) {
1562                         return FALSE;
1563                     }
1564                     int32_t t;
1565                     if (src != limit &&
1566                             0 < (t = ((int32_t)*src - Hangul::JAMO_T_BASE)) &&
1567                             t < Hangul::JAMO_T_COUNT) {
1568                         // The next character is a Jamo T.
1569                         ++src;
1570                     } else if (hasCompBoundaryBefore(src, limit)) {
1571                         // No Jamo T follows, not even via decomposition.
1572                         t = 0;
1573                     } else {
1574                         t = -1;
1575                     }
1576                     if (t >= 0) {
1577                         UChar32 syllable = Hangul::HANGUL_BASE +
1578                             (l*Hangul::JAMO_V_COUNT + (c-Hangul::JAMO_V_BASE)) *
1579                             Hangul::JAMO_T_COUNT + t;
1580                         --prevSrc;  // Replace the Jamo L as well.
1581                         if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1582                             break;
1583                         }
1584                         if(!buffer.appendBMP((UChar)syllable, 0, errorCode)) {
1585                             break;
1586                         }
1587                         prevBoundary = src;
1588                         continue;
1589                     }
1590                     // If we see L+V+x where x!=T then we drop to the slow path,
1591                     // decompose and recompose.
1592                     // This is to deal with NFKC finding normal L and V but a
1593                     // compatibility variant of a T.
1594                     // We need to either fully compose that combination here
1595                     // (which would complicate the code and may not work with strange custom data)
1596                     // or use the slow path.
1597                 }
1598             } else if (Hangul::isHangulLV(prev)) {
1599                 // The current character is a Jamo Trailing consonant,
1600                 // compose with previous Hangul LV that does not contain a Jamo T.
1601                 if (!doCompose) {
1602                     return FALSE;
1603                 }
1604                 UChar32 syllable = prev + c - Hangul::JAMO_T_BASE;
1605                 --prevSrc;  // Replace the Hangul LV as well.
1606                 if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1607                     break;
1608                 }
1609                 if(!buffer.appendBMP((UChar)syllable, 0, errorCode)) {
1610                     break;
1611                 }
1612                 prevBoundary = src;
1613                 continue;
1614             }
1615             // No matching context, or may need to decompose surrounding text first:
1616             // Fall through to the slow path.
1617         } else if (norm16 > JAMO_VT) {  // norm16 >= MIN_YES_YES_WITH_CC
1618             // One or more combining marks that do not combine-back:
1619             // Check for canonical order, copy unchanged if ok and
1620             // if followed by a character with a boundary-before.
1621             uint8_t cc = getCCFromNormalYesOrMaybe(norm16);  // cc!=0
1622             if (onlyContiguous /* FCC */ && getPreviousTrailCC(prevBoundary, prevSrc) > cc) {
1623                 // Fails FCD test, need to decompose and contiguously recompose.
1624                 if (!doCompose) {
1625                     return FALSE;
1626                 }
1627             } else {
1628                 // If !onlyContiguous (not FCC), then we ignore the tccc of
1629                 // the previous character which passed the quick check "yes && ccc==0" test.
1630                 const UChar *nextSrc;
1631                 uint16_t n16;
1632                 for (;;) {
1633                     if (src == limit) {
1634                         if (doCompose) {
1635                             buffer.appendZeroCC(prevBoundary, limit, errorCode);
1636                         }
1637                         return TRUE;
1638                     }
1639                     uint8_t prevCC = cc;
1640                     nextSrc = src;
1641                     UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, c, n16);
1642                     if (n16 >= MIN_YES_YES_WITH_CC) {
1643                         cc = getCCFromNormalYesOrMaybe(n16);
1644                         if (prevCC > cc) {
1645                             if (!doCompose) {
1646                                 return FALSE;
1647                             }
1648                             break;
1649                         }
1650                     } else {
1651                         break;
1652                     }
1653                     src = nextSrc;
1654                 }
1655                 // src is after the last in-order combining mark.
1656                 // If there is a boundary here, then we continue with no change.
1657                 if (norm16HasCompBoundaryBefore(n16)) {
1658                     if (isCompYesAndZeroCC(n16)) {
1659                         src = nextSrc;
1660                     }
1661                     continue;
1662                 }
1663                 // Use the slow path. There is no boundary in [prevSrc, src[.
1664             }
1665         }
1666 
1667         // Slow path: Find the nearest boundaries around the current character,
1668         // decompose and recompose.
1669         if (prevBoundary != prevSrc && !norm16HasCompBoundaryBefore(norm16)) {
1670             const UChar *p = prevSrc;
1671             UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, prevBoundary, p, c, norm16);
1672             if (!norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
1673                 prevSrc = p;
1674             }
1675         }
1676         if (doCompose && prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
1677             break;
1678         }
1679         int32_t recomposeStartIndex=buffer.length();
1680         // We know there is not a boundary here.
1681         decomposeShort(prevSrc, src, FALSE /* !stopAtCompBoundary */, onlyContiguous,
1682                        buffer, errorCode);
1683         // Decompose until the next boundary.
1684         src = decomposeShort(src, limit, TRUE /* stopAtCompBoundary */, onlyContiguous,
1685                              buffer, errorCode);
1686         if (U_FAILURE(errorCode)) {
1687             break;
1688         }
1689         if ((src - prevSrc) > INT32_MAX) {  // guard before buffer.equals()
1690             errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
1691             return TRUE;
1692         }
1693         recompose(buffer, recomposeStartIndex, onlyContiguous);
1694         if(!doCompose) {
1695             if(!buffer.equals(prevSrc, src)) {
1696                 return FALSE;
1697             }
1698             buffer.remove();
1699         }
1700         prevBoundary=src;
1701     }
1702     return TRUE;
1703 }
1704 
1705 // Very similar to compose(): Make the same changes in both places if relevant.
1706 // pQCResult==NULL: spanQuickCheckYes
1707 // pQCResult!=NULL: quickCheck (*pQCResult must be UNORM_YES)
1708 const UChar *
composeQuickCheck(const UChar * src,const UChar * limit,UBool onlyContiguous,UNormalizationCheckResult * pQCResult) const1709 Normalizer2Impl::composeQuickCheck(const UChar *src, const UChar *limit,
1710                                    UBool onlyContiguous,
1711                                    UNormalizationCheckResult *pQCResult) const {
1712     const UChar *prevBoundary=src;
1713     UChar32 minNoMaybeCP=minCompNoMaybeCP;
1714     if(limit==NULL) {
1715         UErrorCode errorCode=U_ZERO_ERROR;
1716         src=copyLowPrefixFromNulTerminated(src, minNoMaybeCP, NULL, errorCode);
1717         limit=u_strchr(src, 0);
1718         if (prevBoundary != src) {
1719             if (hasCompBoundaryAfter(*(src-1), onlyContiguous)) {
1720                 prevBoundary = src;
1721             } else {
1722                 prevBoundary = --src;
1723             }
1724         }
1725     }
1726 
1727     for(;;) {
1728         // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
1729         // or with (compYes && ccc==0) properties.
1730         const UChar *prevSrc;
1731         UChar32 c = 0;
1732         uint16_t norm16 = 0;
1733         for (;;) {
1734             if(src==limit) {
1735                 return src;
1736             }
1737             if( (c=*src)<minNoMaybeCP ||
1738                 isCompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c))
1739             ) {
1740                 ++src;
1741             } else {
1742                 prevSrc = src++;
1743                 if(!U16_IS_LEAD(c)) {
1744                     break;
1745                 } else {
1746                     UChar c2;
1747                     if(src!=limit && U16_IS_TRAIL(c2=*src)) {
1748                         ++src;
1749                         c=U16_GET_SUPPLEMENTARY(c, c2);
1750                         norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c);
1751                         if(!isCompYesAndZeroCC(norm16)) {
1752                             break;
1753                         }
1754                     }
1755                 }
1756             }
1757         }
1758         // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
1759         // The current character is either a "noNo" (has a mapping)
1760         // or a "maybeYes" (combines backward)
1761         // or a "yesYes" with ccc!=0.
1762         // It is not a Hangul syllable or Jamo L because those have "yes" properties.
1763 
1764         uint16_t prevNorm16 = INERT;
1765         if (prevBoundary != prevSrc) {
1766             if (norm16HasCompBoundaryBefore(norm16)) {
1767                 prevBoundary = prevSrc;
1768             } else {
1769                 const UChar *p = prevSrc;
1770                 uint16_t n16;
1771                 UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, prevBoundary, p, c, n16);
1772                 if (norm16HasCompBoundaryAfter(n16, onlyContiguous)) {
1773                     prevBoundary = prevSrc;
1774                 } else {
1775                     prevBoundary = p;
1776                     prevNorm16 = n16;
1777                 }
1778             }
1779         }
1780 
1781         if(isMaybeOrNonZeroCC(norm16)) {
1782             uint8_t cc=getCCFromYesOrMaybe(norm16);
1783             if (onlyContiguous /* FCC */ && cc != 0 &&
1784                     getTrailCCFromCompYesAndZeroCC(prevNorm16) > cc) {
1785                 // The [prevBoundary..prevSrc[ character
1786                 // passed the quick check "yes && ccc==0" test
1787                 // but is out of canonical order with the current combining mark.
1788             } else {
1789                 // If !onlyContiguous (not FCC), then we ignore the tccc of
1790                 // the previous character which passed the quick check "yes && ccc==0" test.
1791                 const UChar *nextSrc;
1792                 for (;;) {
1793                     if (norm16 < MIN_YES_YES_WITH_CC) {
1794                         if (pQCResult != nullptr) {
1795                             *pQCResult = UNORM_MAYBE;
1796                         } else {
1797                             return prevBoundary;
1798                         }
1799                     }
1800                     if (src == limit) {
1801                         return src;
1802                     }
1803                     uint8_t prevCC = cc;
1804                     nextSrc = src;
1805                     UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, c, norm16);
1806                     if (isMaybeOrNonZeroCC(norm16)) {
1807                         cc = getCCFromYesOrMaybe(norm16);
1808                         if (!(prevCC <= cc || cc == 0)) {
1809                             break;
1810                         }
1811                     } else {
1812                         break;
1813                     }
1814                     src = nextSrc;
1815                 }
1816                 // src is after the last in-order combining mark.
1817                 if (isCompYesAndZeroCC(norm16)) {
1818                     prevBoundary = src;
1819                     src = nextSrc;
1820                     continue;
1821                 }
1822             }
1823         }
1824         if(pQCResult!=NULL) {
1825             *pQCResult=UNORM_NO;
1826         }
1827         return prevBoundary;
1828     }
1829 }
1830 
composeAndAppend(const UChar * src,const UChar * limit,UBool doCompose,UBool onlyContiguous,UnicodeString & safeMiddle,ReorderingBuffer & buffer,UErrorCode & errorCode) const1831 void Normalizer2Impl::composeAndAppend(const UChar *src, const UChar *limit,
1832                                        UBool doCompose,
1833                                        UBool onlyContiguous,
1834                                        UnicodeString &safeMiddle,
1835                                        ReorderingBuffer &buffer,
1836                                        UErrorCode &errorCode) const {
1837     if(!buffer.isEmpty()) {
1838         const UChar *firstStarterInSrc=findNextCompBoundary(src, limit, onlyContiguous);
1839         if(src!=firstStarterInSrc) {
1840             const UChar *lastStarterInDest=findPreviousCompBoundary(buffer.getStart(),
1841                                                                     buffer.getLimit(), onlyContiguous);
1842             int32_t destSuffixLength=(int32_t)(buffer.getLimit()-lastStarterInDest);
1843             UnicodeString middle(lastStarterInDest, destSuffixLength);
1844             buffer.removeSuffix(destSuffixLength);
1845             safeMiddle=middle;
1846             middle.append(src, (int32_t)(firstStarterInSrc-src));
1847             const UChar *middleStart=middle.getBuffer();
1848             compose(middleStart, middleStart+middle.length(), onlyContiguous,
1849                     TRUE, buffer, errorCode);
1850             if(U_FAILURE(errorCode)) {
1851                 return;
1852             }
1853             src=firstStarterInSrc;
1854         }
1855     }
1856     if(doCompose) {
1857         compose(src, limit, onlyContiguous, TRUE, buffer, errorCode);
1858     } else {
1859         if(limit==NULL) {  // appendZeroCC() needs limit!=NULL
1860             limit=u_strchr(src, 0);
1861         }
1862         buffer.appendZeroCC(src, limit, errorCode);
1863     }
1864 }
1865 
1866 UBool
composeUTF8(uint32_t options,UBool onlyContiguous,const uint8_t * src,const uint8_t * limit,ByteSink * sink,Edits * edits,UErrorCode & errorCode) const1867 Normalizer2Impl::composeUTF8(uint32_t options, UBool onlyContiguous,
1868                              const uint8_t *src, const uint8_t *limit,
1869                              ByteSink *sink, Edits *edits, UErrorCode &errorCode) const {
1870     U_ASSERT(limit != nullptr);
1871     UnicodeString s16;
1872     uint8_t minNoMaybeLead = leadByteForCP(minCompNoMaybeCP);
1873     const uint8_t *prevBoundary = src;
1874 
1875     for (;;) {
1876         // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
1877         // or with (compYes && ccc==0) properties.
1878         const uint8_t *prevSrc;
1879         uint16_t norm16 = 0;
1880         for (;;) {
1881             if (src == limit) {
1882                 if (prevBoundary != limit && sink != nullptr) {
1883                     ByteSinkUtil::appendUnchanged(prevBoundary, limit,
1884                                                   *sink, options, edits, errorCode);
1885                 }
1886                 return TRUE;
1887             }
1888             if (*src < minNoMaybeLead) {
1889                 ++src;
1890             } else {
1891                 prevSrc = src;
1892                 UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16);
1893                 if (!isCompYesAndZeroCC(norm16)) {
1894                     break;
1895                 }
1896             }
1897         }
1898         // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
1899         // The current character is either a "noNo" (has a mapping)
1900         // or a "maybeYes" (combines backward)
1901         // or a "yesYes" with ccc!=0.
1902         // It is not a Hangul syllable or Jamo L because those have "yes" properties.
1903 
1904         // Medium-fast path: Handle cases that do not require full decomposition and recomposition.
1905         if (!isMaybeOrNonZeroCC(norm16)) {  // minNoNo <= norm16 < minMaybeYes
1906             if (sink == nullptr) {
1907                 return FALSE;
1908             }
1909             // Fast path for mapping a character that is immediately surrounded by boundaries.
1910             // In this case, we need not decompose around the current character.
1911             if (isDecompNoAlgorithmic(norm16)) {
1912                 // Maps to a single isCompYesAndZeroCC character
1913                 // which also implies hasCompBoundaryBefore.
1914                 if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
1915                         hasCompBoundaryBefore(src, limit)) {
1916                     if (prevBoundary != prevSrc &&
1917                             !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
1918                                                            *sink, options, edits, errorCode)) {
1919                         break;
1920                     }
1921                     appendCodePointDelta(prevSrc, src, getAlgorithmicDelta(norm16), *sink, edits);
1922                     prevBoundary = src;
1923                     continue;
1924                 }
1925             } else if (norm16 < minNoNoCompBoundaryBefore) {
1926                 // The mapping is comp-normalized which also implies hasCompBoundaryBefore.
1927                 if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
1928                         hasCompBoundaryBefore(src, limit)) {
1929                     if (prevBoundary != prevSrc &&
1930                             !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
1931                                                            *sink, options, edits, errorCode)) {
1932                         break;
1933                     }
1934                     const uint16_t *mapping = getMapping(norm16);
1935                     int32_t length = *mapping++ & MAPPING_LENGTH_MASK;
1936                     if (!ByteSinkUtil::appendChange(prevSrc, src, (const UChar *)mapping, length,
1937                                                     *sink, edits, errorCode)) {
1938                         break;
1939                     }
1940                     prevBoundary = src;
1941                     continue;
1942                 }
1943             } else if (norm16 >= minNoNoEmpty) {
1944                 // The current character maps to nothing.
1945                 // Simply omit it from the output if there is a boundary before _or_ after it.
1946                 // The character itself implies no boundaries.
1947                 if (hasCompBoundaryBefore(src, limit) ||
1948                         hasCompBoundaryAfter(prevBoundary, prevSrc, onlyContiguous)) {
1949                     if (prevBoundary != prevSrc &&
1950                             !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
1951                                                            *sink, options, edits, errorCode)) {
1952                         break;
1953                     }
1954                     if (edits != nullptr) {
1955                         edits->addReplace((int32_t)(src - prevSrc), 0);
1956                     }
1957                     prevBoundary = src;
1958                     continue;
1959                 }
1960             }
1961             // Other "noNo" type, or need to examine more text around this character:
1962             // Fall through to the slow path.
1963         } else if (isJamoVT(norm16)) {
1964             // Jamo L: E1 84 80..92
1965             // Jamo V: E1 85 A1..B5
1966             // Jamo T: E1 86 A8..E1 87 82
1967             U_ASSERT((src - prevSrc) == 3 && *prevSrc == 0xe1);
1968             UChar32 prev = previousHangulOrJamo(prevBoundary, prevSrc);
1969             if (prevSrc[1] == 0x85) {
1970                 // The current character is a Jamo Vowel,
1971                 // compose with previous Jamo L and following Jamo T.
1972                 UChar32 l = prev - Hangul::JAMO_L_BASE;
1973                 if ((uint32_t)l < Hangul::JAMO_L_COUNT) {
1974                     if (sink == nullptr) {
1975                         return FALSE;
1976                     }
1977                     int32_t t = getJamoTMinusBase(src, limit);
1978                     if (t >= 0) {
1979                         // The next character is a Jamo T.
1980                         src += 3;
1981                     } else if (hasCompBoundaryBefore(src, limit)) {
1982                         // No Jamo T follows, not even via decomposition.
1983                         t = 0;
1984                     }
1985                     if (t >= 0) {
1986                         UChar32 syllable = Hangul::HANGUL_BASE +
1987                             (l*Hangul::JAMO_V_COUNT + (prevSrc[2]-0xa1)) *
1988                             Hangul::JAMO_T_COUNT + t;
1989                         prevSrc -= 3;  // Replace the Jamo L as well.
1990                         if (prevBoundary != prevSrc &&
1991                                 !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
1992                                                                *sink, options, edits, errorCode)) {
1993                             break;
1994                         }
1995                         ByteSinkUtil::appendCodePoint(prevSrc, src, syllable, *sink, edits);
1996                         prevBoundary = src;
1997                         continue;
1998                     }
1999                     // If we see L+V+x where x!=T then we drop to the slow path,
2000                     // decompose and recompose.
2001                     // This is to deal with NFKC finding normal L and V but a
2002                     // compatibility variant of a T.
2003                     // We need to either fully compose that combination here
2004                     // (which would complicate the code and may not work with strange custom data)
2005                     // or use the slow path.
2006                 }
2007             } else if (Hangul::isHangulLV(prev)) {
2008                 // The current character is a Jamo Trailing consonant,
2009                 // compose with previous Hangul LV that does not contain a Jamo T.
2010                 if (sink == nullptr) {
2011                     return FALSE;
2012                 }
2013                 UChar32 syllable = prev + getJamoTMinusBase(prevSrc, src);
2014                 prevSrc -= 3;  // Replace the Hangul LV as well.
2015                 if (prevBoundary != prevSrc &&
2016                         !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
2017                                                        *sink, options, edits, errorCode)) {
2018                     break;
2019                 }
2020                 ByteSinkUtil::appendCodePoint(prevSrc, src, syllable, *sink, edits);
2021                 prevBoundary = src;
2022                 continue;
2023             }
2024             // No matching context, or may need to decompose surrounding text first:
2025             // Fall through to the slow path.
2026         } else if (norm16 > JAMO_VT) {  // norm16 >= MIN_YES_YES_WITH_CC
2027             // One or more combining marks that do not combine-back:
2028             // Check for canonical order, copy unchanged if ok and
2029             // if followed by a character with a boundary-before.
2030             uint8_t cc = getCCFromNormalYesOrMaybe(norm16);  // cc!=0
2031             if (onlyContiguous /* FCC */ && getPreviousTrailCC(prevBoundary, prevSrc) > cc) {
2032                 // Fails FCD test, need to decompose and contiguously recompose.
2033                 if (sink == nullptr) {
2034                     return FALSE;
2035                 }
2036             } else {
2037                 // If !onlyContiguous (not FCC), then we ignore the tccc of
2038                 // the previous character which passed the quick check "yes && ccc==0" test.
2039                 const uint8_t *nextSrc;
2040                 uint16_t n16;
2041                 for (;;) {
2042                     if (src == limit) {
2043                         if (sink != nullptr) {
2044                             ByteSinkUtil::appendUnchanged(prevBoundary, limit,
2045                                                           *sink, options, edits, errorCode);
2046                         }
2047                         return TRUE;
2048                     }
2049                     uint8_t prevCC = cc;
2050                     nextSrc = src;
2051                     UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, n16);
2052                     if (n16 >= MIN_YES_YES_WITH_CC) {
2053                         cc = getCCFromNormalYesOrMaybe(n16);
2054                         if (prevCC > cc) {
2055                             if (sink == nullptr) {
2056                                 return FALSE;
2057                             }
2058                             break;
2059                         }
2060                     } else {
2061                         break;
2062                     }
2063                     src = nextSrc;
2064                 }
2065                 // src is after the last in-order combining mark.
2066                 // If there is a boundary here, then we continue with no change.
2067                 if (norm16HasCompBoundaryBefore(n16)) {
2068                     if (isCompYesAndZeroCC(n16)) {
2069                         src = nextSrc;
2070                     }
2071                     continue;
2072                 }
2073                 // Use the slow path. There is no boundary in [prevSrc, src[.
2074             }
2075         }
2076 
2077         // Slow path: Find the nearest boundaries around the current character,
2078         // decompose and recompose.
2079         if (prevBoundary != prevSrc && !norm16HasCompBoundaryBefore(norm16)) {
2080             const uint8_t *p = prevSrc;
2081             UCPTRIE_FAST_U8_PREV(normTrie, UCPTRIE_16, prevBoundary, p, norm16);
2082             if (!norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
2083                 prevSrc = p;
2084             }
2085         }
2086         ReorderingBuffer buffer(*this, s16, errorCode);
2087         if (U_FAILURE(errorCode)) {
2088             break;
2089         }
2090         // We know there is not a boundary here.
2091         decomposeShort(prevSrc, src, STOP_AT_LIMIT, onlyContiguous,
2092                        buffer, errorCode);
2093         // Decompose until the next boundary.
2094         src = decomposeShort(src, limit, STOP_AT_COMP_BOUNDARY, onlyContiguous,
2095                              buffer, errorCode);
2096         if (U_FAILURE(errorCode)) {
2097             break;
2098         }
2099         if ((src - prevSrc) > INT32_MAX) {  // guard before buffer.equals()
2100             errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
2101             return TRUE;
2102         }
2103         recompose(buffer, 0, onlyContiguous);
2104         if (!buffer.equals(prevSrc, src)) {
2105             if (sink == nullptr) {
2106                 return FALSE;
2107             }
2108             if (prevBoundary != prevSrc &&
2109                     !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
2110                                                    *sink, options, edits, errorCode)) {
2111                 break;
2112             }
2113             if (!ByteSinkUtil::appendChange(prevSrc, src, buffer.getStart(), buffer.length(),
2114                                             *sink, edits, errorCode)) {
2115                 break;
2116             }
2117             prevBoundary = src;
2118         }
2119     }
2120     return TRUE;
2121 }
2122 
hasCompBoundaryBefore(const UChar * src,const UChar * limit) const2123 UBool Normalizer2Impl::hasCompBoundaryBefore(const UChar *src, const UChar *limit) const {
2124     if (src == limit || *src < minCompNoMaybeCP) {
2125         return TRUE;
2126     }
2127     UChar32 c;
2128     uint16_t norm16;
2129     UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, src, limit, c, norm16);
2130     return norm16HasCompBoundaryBefore(norm16);
2131 }
2132 
hasCompBoundaryBefore(const uint8_t * src,const uint8_t * limit) const2133 UBool Normalizer2Impl::hasCompBoundaryBefore(const uint8_t *src, const uint8_t *limit) const {
2134     if (src == limit) {
2135         return TRUE;
2136     }
2137     uint16_t norm16;
2138     UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16);
2139     return norm16HasCompBoundaryBefore(norm16);
2140 }
2141 
hasCompBoundaryAfter(const UChar * start,const UChar * p,UBool onlyContiguous) const2142 UBool Normalizer2Impl::hasCompBoundaryAfter(const UChar *start, const UChar *p,
2143                                             UBool onlyContiguous) const {
2144     if (start == p) {
2145         return TRUE;
2146     }
2147     UChar32 c;
2148     uint16_t norm16;
2149     UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16);
2150     return norm16HasCompBoundaryAfter(norm16, onlyContiguous);
2151 }
2152 
hasCompBoundaryAfter(const uint8_t * start,const uint8_t * p,UBool onlyContiguous) const2153 UBool Normalizer2Impl::hasCompBoundaryAfter(const uint8_t *start, const uint8_t *p,
2154                                             UBool onlyContiguous) const {
2155     if (start == p) {
2156         return TRUE;
2157     }
2158     uint16_t norm16;
2159     UCPTRIE_FAST_U8_PREV(normTrie, UCPTRIE_16, start, p, norm16);
2160     return norm16HasCompBoundaryAfter(norm16, onlyContiguous);
2161 }
2162 
findPreviousCompBoundary(const UChar * start,const UChar * p,UBool onlyContiguous) const2163 const UChar *Normalizer2Impl::findPreviousCompBoundary(const UChar *start, const UChar *p,
2164                                                        UBool onlyContiguous) const {
2165     while (p != start) {
2166         const UChar *codePointLimit = p;
2167         UChar32 c;
2168         uint16_t norm16;
2169         UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16);
2170         if (norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
2171             return codePointLimit;
2172         }
2173         if (hasCompBoundaryBefore(c, norm16)) {
2174             return p;
2175         }
2176     }
2177     return p;
2178 }
2179 
findNextCompBoundary(const UChar * p,const UChar * limit,UBool onlyContiguous) const2180 const UChar *Normalizer2Impl::findNextCompBoundary(const UChar *p, const UChar *limit,
2181                                                    UBool onlyContiguous) const {
2182     while (p != limit) {
2183         const UChar *codePointStart = p;
2184         UChar32 c;
2185         uint16_t norm16;
2186         UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16);
2187         if (hasCompBoundaryBefore(c, norm16)) {
2188             return codePointStart;
2189         }
2190         if (norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
2191             return p;
2192         }
2193     }
2194     return p;
2195 }
2196 
getPreviousTrailCC(const UChar * start,const UChar * p) const2197 uint8_t Normalizer2Impl::getPreviousTrailCC(const UChar *start, const UChar *p) const {
2198     if (start == p) {
2199         return 0;
2200     }
2201     int32_t i = (int32_t)(p - start);
2202     UChar32 c;
2203     U16_PREV(start, 0, i, c);
2204     return (uint8_t)getFCD16(c);
2205 }
2206 
getPreviousTrailCC(const uint8_t * start,const uint8_t * p) const2207 uint8_t Normalizer2Impl::getPreviousTrailCC(const uint8_t *start, const uint8_t *p) const {
2208     if (start == p) {
2209         return 0;
2210     }
2211     int32_t i = (int32_t)(p - start);
2212     UChar32 c;
2213     U8_PREV(start, 0, i, c);
2214     return (uint8_t)getFCD16(c);
2215 }
2216 
2217 // Note: normalizer2impl.cpp r30982 (2011-nov-27)
2218 // still had getFCDTrie() which built and cached an FCD trie.
2219 // That provided faster access to FCD data than getFCD16FromNormData()
2220 // but required synchronization and consumed some 10kB of heap memory
2221 // in any process that uses FCD (e.g., via collation).
2222 // minDecompNoCP etc. and smallFCD[] are intended to help with any loss of performance,
2223 // at least for ASCII & CJK.
2224 
2225 // Ticket 20907 - The optimizer in MSVC/Visual Studio versions below 16.4 has trouble with this
2226 // function on Windows ARM64. As a work-around, we disable optimizations for this function.
2227 // This work-around could/should be removed once the following versions of Visual Studio are no
2228 // longer supported: All versions of VS2017, and versions of VS2019 below 16.4.
2229 #if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
2230 #pragma optimize( "", off )
2231 #endif
2232 // Gets the FCD value from the regular normalization data.
getFCD16FromNormData(UChar32 c) const2233 uint16_t Normalizer2Impl::getFCD16FromNormData(UChar32 c) const {
2234     uint16_t norm16=getNorm16(c);
2235     if (norm16 >= limitNoNo) {
2236         if(norm16>=MIN_NORMAL_MAYBE_YES) {
2237             // combining mark
2238             norm16=getCCFromNormalYesOrMaybe(norm16);
2239             return norm16|(norm16<<8);
2240         } else if(norm16>=minMaybeYes) {
2241             return 0;
2242         } else {  // isDecompNoAlgorithmic(norm16)
2243             uint16_t deltaTrailCC = norm16 & DELTA_TCCC_MASK;
2244             if (deltaTrailCC <= DELTA_TCCC_1) {
2245                 return deltaTrailCC >> OFFSET_SHIFT;
2246             }
2247             // Maps to an isCompYesAndZeroCC.
2248             c=mapAlgorithmic(c, norm16);
2249             norm16=getRawNorm16(c);
2250         }
2251     }
2252     if(norm16<=minYesNo || isHangulLVT(norm16)) {
2253         // no decomposition or Hangul syllable, all zeros
2254         return 0;
2255     }
2256     // c decomposes, get everything from the variable-length extra data
2257     const uint16_t *mapping=getMapping(norm16);
2258     uint16_t firstUnit=*mapping;
2259     norm16=firstUnit>>8;  // tccc
2260     if(firstUnit&MAPPING_HAS_CCC_LCCC_WORD) {
2261         norm16|=*(mapping-1)&0xff00;  // lccc
2262     }
2263     return norm16;
2264 }
2265 #if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
2266 #pragma optimize( "", on )
2267 #endif
2268 
2269 // Dual functionality:
2270 // buffer!=NULL: normalize
2271 // buffer==NULL: isNormalized/quickCheck/spanQuickCheckYes
2272 const UChar *
makeFCD(const UChar * src,const UChar * limit,ReorderingBuffer * buffer,UErrorCode & errorCode) const2273 Normalizer2Impl::makeFCD(const UChar *src, const UChar *limit,
2274                          ReorderingBuffer *buffer,
2275                          UErrorCode &errorCode) const {
2276     // Tracks the last FCD-safe boundary, before lccc=0 or after properly-ordered tccc<=1.
2277     // Similar to the prevBoundary in the compose() implementation.
2278     const UChar *prevBoundary=src;
2279     int32_t prevFCD16=0;
2280     if(limit==NULL) {
2281         src=copyLowPrefixFromNulTerminated(src, minLcccCP, buffer, errorCode);
2282         if(U_FAILURE(errorCode)) {
2283             return src;
2284         }
2285         if(prevBoundary<src) {
2286             prevBoundary=src;
2287             // We know that the previous character's lccc==0.
2288             // Fetching the fcd16 value was deferred for this below-U+0300 code point.
2289             prevFCD16=getFCD16(*(src-1));
2290             if(prevFCD16>1) {
2291                 --prevBoundary;
2292             }
2293         }
2294         limit=u_strchr(src, 0);
2295     }
2296 
2297     // Note: In this function we use buffer->appendZeroCC() because we track
2298     // the lead and trail combining classes here, rather than leaving it to
2299     // the ReorderingBuffer.
2300     // The exception is the call to decomposeShort() which uses the buffer
2301     // in the normal way.
2302 
2303     const UChar *prevSrc;
2304     UChar32 c=0;
2305     uint16_t fcd16=0;
2306 
2307     for(;;) {
2308         // count code units with lccc==0
2309         for(prevSrc=src; src!=limit;) {
2310             if((c=*src)<minLcccCP) {
2311                 prevFCD16=~c;
2312                 ++src;
2313             } else if(!singleLeadMightHaveNonZeroFCD16(c)) {
2314                 prevFCD16=0;
2315                 ++src;
2316             } else {
2317                 if(U16_IS_LEAD(c)) {
2318                     UChar c2;
2319                     if((src+1)!=limit && U16_IS_TRAIL(c2=src[1])) {
2320                         c=U16_GET_SUPPLEMENTARY(c, c2);
2321                     }
2322                 }
2323                 if((fcd16=getFCD16FromNormData(c))<=0xff) {
2324                     prevFCD16=fcd16;
2325                     src+=U16_LENGTH(c);
2326                 } else {
2327                     break;
2328                 }
2329             }
2330         }
2331         // copy these code units all at once
2332         if(src!=prevSrc) {
2333             if(buffer!=NULL && !buffer->appendZeroCC(prevSrc, src, errorCode)) {
2334                 break;
2335             }
2336             if(src==limit) {
2337                 break;
2338             }
2339             prevBoundary=src;
2340             // We know that the previous character's lccc==0.
2341             if(prevFCD16<0) {
2342                 // Fetching the fcd16 value was deferred for this below-minLcccCP code point.
2343                 UChar32 prev=~prevFCD16;
2344                 if(prev<minDecompNoCP) {
2345                     prevFCD16=0;
2346                 } else {
2347                     prevFCD16=getFCD16FromNormData(prev);
2348                     if(prevFCD16>1) {
2349                         --prevBoundary;
2350                     }
2351                 }
2352             } else {
2353                 const UChar *p=src-1;
2354                 if(U16_IS_TRAIL(*p) && prevSrc<p && U16_IS_LEAD(*(p-1))) {
2355                     --p;
2356                     // Need to fetch the previous character's FCD value because
2357                     // prevFCD16 was just for the trail surrogate code point.
2358                     prevFCD16=getFCD16FromNormData(U16_GET_SUPPLEMENTARY(p[0], p[1]));
2359                     // Still known to have lccc==0 because its lead surrogate unit had lccc==0.
2360                 }
2361                 if(prevFCD16>1) {
2362                     prevBoundary=p;
2363                 }
2364             }
2365             // The start of the current character (c).
2366             prevSrc=src;
2367         } else if(src==limit) {
2368             break;
2369         }
2370 
2371         src+=U16_LENGTH(c);
2372         // The current character (c) at [prevSrc..src[ has a non-zero lead combining class.
2373         // Check for proper order, and decompose locally if necessary.
2374         if((prevFCD16&0xff)<=(fcd16>>8)) {
2375             // proper order: prev tccc <= current lccc
2376             if((fcd16&0xff)<=1) {
2377                 prevBoundary=src;
2378             }
2379             if(buffer!=NULL && !buffer->appendZeroCC(c, errorCode)) {
2380                 break;
2381             }
2382             prevFCD16=fcd16;
2383             continue;
2384         } else if(buffer==NULL) {
2385             return prevBoundary;  // quick check "no"
2386         } else {
2387             /*
2388              * Back out the part of the source that we copied or appended
2389              * already but is now going to be decomposed.
2390              * prevSrc is set to after what was copied/appended.
2391              */
2392             buffer->removeSuffix((int32_t)(prevSrc-prevBoundary));
2393             /*
2394              * Find the part of the source that needs to be decomposed,
2395              * up to the next safe boundary.
2396              */
2397             src=findNextFCDBoundary(src, limit);
2398             /*
2399              * The source text does not fulfill the conditions for FCD.
2400              * Decompose and reorder a limited piece of the text.
2401              */
2402             decomposeShort(prevBoundary, src, FALSE, FALSE, *buffer, errorCode);
2403             if (U_FAILURE(errorCode)) {
2404                 break;
2405             }
2406             prevBoundary=src;
2407             prevFCD16=0;
2408         }
2409     }
2410     return src;
2411 }
2412 
makeFCDAndAppend(const UChar * src,const UChar * limit,UBool doMakeFCD,UnicodeString & safeMiddle,ReorderingBuffer & buffer,UErrorCode & errorCode) const2413 void Normalizer2Impl::makeFCDAndAppend(const UChar *src, const UChar *limit,
2414                                        UBool doMakeFCD,
2415                                        UnicodeString &safeMiddle,
2416                                        ReorderingBuffer &buffer,
2417                                        UErrorCode &errorCode) const {
2418     if(!buffer.isEmpty()) {
2419         const UChar *firstBoundaryInSrc=findNextFCDBoundary(src, limit);
2420         if(src!=firstBoundaryInSrc) {
2421             const UChar *lastBoundaryInDest=findPreviousFCDBoundary(buffer.getStart(),
2422                                                                     buffer.getLimit());
2423             int32_t destSuffixLength=(int32_t)(buffer.getLimit()-lastBoundaryInDest);
2424             UnicodeString middle(lastBoundaryInDest, destSuffixLength);
2425             buffer.removeSuffix(destSuffixLength);
2426             safeMiddle=middle;
2427             middle.append(src, (int32_t)(firstBoundaryInSrc-src));
2428             const UChar *middleStart=middle.getBuffer();
2429             makeFCD(middleStart, middleStart+middle.length(), &buffer, errorCode);
2430             if(U_FAILURE(errorCode)) {
2431                 return;
2432             }
2433             src=firstBoundaryInSrc;
2434         }
2435     }
2436     if(doMakeFCD) {
2437         makeFCD(src, limit, &buffer, errorCode);
2438     } else {
2439         if(limit==NULL) {  // appendZeroCC() needs limit!=NULL
2440             limit=u_strchr(src, 0);
2441         }
2442         buffer.appendZeroCC(src, limit, errorCode);
2443     }
2444 }
2445 
findPreviousFCDBoundary(const UChar * start,const UChar * p) const2446 const UChar *Normalizer2Impl::findPreviousFCDBoundary(const UChar *start, const UChar *p) const {
2447     while(start<p) {
2448         const UChar *codePointLimit = p;
2449         UChar32 c;
2450         uint16_t norm16;
2451         UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16);
2452         if (c < minDecompNoCP || norm16HasDecompBoundaryAfter(norm16)) {
2453             return codePointLimit;
2454         }
2455         if (norm16HasDecompBoundaryBefore(norm16)) {
2456             return p;
2457         }
2458     }
2459     return p;
2460 }
2461 
findNextFCDBoundary(const UChar * p,const UChar * limit) const2462 const UChar *Normalizer2Impl::findNextFCDBoundary(const UChar *p, const UChar *limit) const {
2463     while(p<limit) {
2464         const UChar *codePointStart=p;
2465         UChar32 c;
2466         uint16_t norm16;
2467         UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16);
2468         if (c < minLcccCP || norm16HasDecompBoundaryBefore(norm16)) {
2469             return codePointStart;
2470         }
2471         if (norm16HasDecompBoundaryAfter(norm16)) {
2472             return p;
2473         }
2474     }
2475     return p;
2476 }
2477 
2478 // CanonicalIterator data -------------------------------------------------- ***
2479 
CanonIterData(UErrorCode & errorCode)2480 CanonIterData::CanonIterData(UErrorCode &errorCode) :
2481         mutableTrie(umutablecptrie_open(0, 0, &errorCode)), trie(nullptr),
2482         canonStartSets(uprv_deleteUObject, NULL, errorCode) {}
2483 
~CanonIterData()2484 CanonIterData::~CanonIterData() {
2485     umutablecptrie_close(mutableTrie);
2486     ucptrie_close(trie);
2487 }
2488 
addToStartSet(UChar32 origin,UChar32 decompLead,UErrorCode & errorCode)2489 void CanonIterData::addToStartSet(UChar32 origin, UChar32 decompLead, UErrorCode &errorCode) {
2490     uint32_t canonValue = umutablecptrie_get(mutableTrie, decompLead);
2491     if((canonValue&(CANON_HAS_SET|CANON_VALUE_MASK))==0 && origin!=0) {
2492         // origin is the first character whose decomposition starts with
2493         // the character for which we are setting the value.
2494         umutablecptrie_set(mutableTrie, decompLead, canonValue|origin, &errorCode);
2495     } else {
2496         // origin is not the first character, or it is U+0000.
2497         UnicodeSet *set;
2498         if((canonValue&CANON_HAS_SET)==0) {
2499             set=new UnicodeSet;
2500             if(set==NULL) {
2501                 errorCode=U_MEMORY_ALLOCATION_ERROR;
2502                 return;
2503             }
2504             UChar32 firstOrigin=(UChar32)(canonValue&CANON_VALUE_MASK);
2505             canonValue=(canonValue&~CANON_VALUE_MASK)|CANON_HAS_SET|(uint32_t)canonStartSets.size();
2506             umutablecptrie_set(mutableTrie, decompLead, canonValue, &errorCode);
2507             canonStartSets.addElement(set, errorCode);
2508             if(firstOrigin!=0) {
2509                 set->add(firstOrigin);
2510             }
2511         } else {
2512             set=(UnicodeSet *)canonStartSets[(int32_t)(canonValue&CANON_VALUE_MASK)];
2513         }
2514         set->add(origin);
2515     }
2516 }
2517 
2518 // C++ class for friend access to private Normalizer2Impl members.
2519 class InitCanonIterData {
2520 public:
2521     static void doInit(Normalizer2Impl *impl, UErrorCode &errorCode);
2522 };
2523 
2524 U_CDECL_BEGIN
2525 
2526 // UInitOnce instantiation function for CanonIterData
2527 static void U_CALLCONV
initCanonIterData(Normalizer2Impl * impl,UErrorCode & errorCode)2528 initCanonIterData(Normalizer2Impl *impl, UErrorCode &errorCode) {
2529     InitCanonIterData::doInit(impl, errorCode);
2530 }
2531 
2532 U_CDECL_END
2533 
doInit(Normalizer2Impl * impl,UErrorCode & errorCode)2534 void InitCanonIterData::doInit(Normalizer2Impl *impl, UErrorCode &errorCode) {
2535     U_ASSERT(impl->fCanonIterData == NULL);
2536     impl->fCanonIterData = new CanonIterData(errorCode);
2537     if (impl->fCanonIterData == NULL) {
2538         errorCode=U_MEMORY_ALLOCATION_ERROR;
2539     }
2540     if (U_SUCCESS(errorCode)) {
2541         UChar32 start = 0, end;
2542         uint32_t value;
2543         while ((end = ucptrie_getRange(impl->normTrie, start,
2544                                        UCPMAP_RANGE_FIXED_LEAD_SURROGATES, Normalizer2Impl::INERT,
2545                                        nullptr, nullptr, &value)) >= 0) {
2546             // Call Normalizer2Impl::makeCanonIterDataFromNorm16() for a range of same-norm16 characters.
2547             if (value != Normalizer2Impl::INERT) {
2548                 impl->makeCanonIterDataFromNorm16(start, end, value, *impl->fCanonIterData, errorCode);
2549             }
2550             start = end + 1;
2551         }
2552 #ifdef UCPTRIE_DEBUG
2553         umutablecptrie_setName(impl->fCanonIterData->mutableTrie, "CanonIterData");
2554 #endif
2555         impl->fCanonIterData->trie = umutablecptrie_buildImmutable(
2556             impl->fCanonIterData->mutableTrie, UCPTRIE_TYPE_SMALL, UCPTRIE_VALUE_BITS_32, &errorCode);
2557         umutablecptrie_close(impl->fCanonIterData->mutableTrie);
2558         impl->fCanonIterData->mutableTrie = nullptr;
2559     }
2560     if (U_FAILURE(errorCode)) {
2561         delete impl->fCanonIterData;
2562         impl->fCanonIterData = NULL;
2563     }
2564 }
2565 
makeCanonIterDataFromNorm16(UChar32 start,UChar32 end,const uint16_t norm16,CanonIterData & newData,UErrorCode & errorCode) const2566 void Normalizer2Impl::makeCanonIterDataFromNorm16(UChar32 start, UChar32 end, const uint16_t norm16,
2567                                                   CanonIterData &newData,
2568                                                   UErrorCode &errorCode) const {
2569     if(isInert(norm16) || (minYesNo<=norm16 && norm16<minNoNo)) {
2570         // Inert, or 2-way mapping (including Hangul syllable).
2571         // We do not write a canonStartSet for any yesNo character.
2572         // Composites from 2-way mappings are added at runtime from the
2573         // starter's compositions list, and the other characters in
2574         // 2-way mappings get CANON_NOT_SEGMENT_STARTER set because they are
2575         // "maybe" characters.
2576         return;
2577     }
2578     for(UChar32 c=start; c<=end; ++c) {
2579         uint32_t oldValue = umutablecptrie_get(newData.mutableTrie, c);
2580         uint32_t newValue=oldValue;
2581         if(isMaybeOrNonZeroCC(norm16)) {
2582             // not a segment starter if it occurs in a decomposition or has cc!=0
2583             newValue|=CANON_NOT_SEGMENT_STARTER;
2584             if(norm16<MIN_NORMAL_MAYBE_YES) {
2585                 newValue|=CANON_HAS_COMPOSITIONS;
2586             }
2587         } else if(norm16<minYesNo) {
2588             newValue|=CANON_HAS_COMPOSITIONS;
2589         } else {
2590             // c has a one-way decomposition
2591             UChar32 c2=c;
2592             // Do not modify the whole-range norm16 value.
2593             uint16_t norm16_2=norm16;
2594             if (isDecompNoAlgorithmic(norm16_2)) {
2595                 // Maps to an isCompYesAndZeroCC.
2596                 c2 = mapAlgorithmic(c2, norm16_2);
2597                 norm16_2 = getRawNorm16(c2);
2598                 // No compatibility mappings for the CanonicalIterator.
2599                 U_ASSERT(!(isHangulLV(norm16_2) || isHangulLVT(norm16_2)));
2600             }
2601             if (norm16_2 > minYesNo) {
2602                 // c decomposes, get everything from the variable-length extra data
2603                 const uint16_t *mapping=getMapping(norm16_2);
2604                 uint16_t firstUnit=*mapping;
2605                 int32_t length=firstUnit&MAPPING_LENGTH_MASK;
2606                 if((firstUnit&MAPPING_HAS_CCC_LCCC_WORD)!=0) {
2607                     if(c==c2 && (*(mapping-1)&0xff)!=0) {
2608                         newValue|=CANON_NOT_SEGMENT_STARTER;  // original c has cc!=0
2609                     }
2610                 }
2611                 // Skip empty mappings (no characters in the decomposition).
2612                 if(length!=0) {
2613                     ++mapping;  // skip over the firstUnit
2614                     // add c to first code point's start set
2615                     int32_t i=0;
2616                     U16_NEXT_UNSAFE(mapping, i, c2);
2617                     newData.addToStartSet(c, c2, errorCode);
2618                     // Set CANON_NOT_SEGMENT_STARTER for each remaining code point of a
2619                     // one-way mapping. A 2-way mapping is possible here after
2620                     // intermediate algorithmic mapping.
2621                     if(norm16_2>=minNoNo) {
2622                         while(i<length) {
2623                             U16_NEXT_UNSAFE(mapping, i, c2);
2624                             uint32_t c2Value = umutablecptrie_get(newData.mutableTrie, c2);
2625                             if((c2Value&CANON_NOT_SEGMENT_STARTER)==0) {
2626                                 umutablecptrie_set(newData.mutableTrie, c2,
2627                                                    c2Value|CANON_NOT_SEGMENT_STARTER, &errorCode);
2628                             }
2629                         }
2630                     }
2631                 }
2632             } else {
2633                 // c decomposed to c2 algorithmically; c has cc==0
2634                 newData.addToStartSet(c, c2, errorCode);
2635             }
2636         }
2637         if(newValue!=oldValue) {
2638             umutablecptrie_set(newData.mutableTrie, c, newValue, &errorCode);
2639         }
2640     }
2641 }
2642 
ensureCanonIterData(UErrorCode & errorCode) const2643 UBool Normalizer2Impl::ensureCanonIterData(UErrorCode &errorCode) const {
2644     // Logically const: Synchronized instantiation.
2645     Normalizer2Impl *me=const_cast<Normalizer2Impl *>(this);
2646     umtx_initOnce(me->fCanonIterDataInitOnce, &initCanonIterData, me, errorCode);
2647     return U_SUCCESS(errorCode);
2648 }
2649 
getCanonValue(UChar32 c) const2650 int32_t Normalizer2Impl::getCanonValue(UChar32 c) const {
2651     return (int32_t)ucptrie_get(fCanonIterData->trie, c);
2652 }
2653 
getCanonStartSet(int32_t n) const2654 const UnicodeSet &Normalizer2Impl::getCanonStartSet(int32_t n) const {
2655     return *(const UnicodeSet *)fCanonIterData->canonStartSets[n];
2656 }
2657 
isCanonSegmentStarter(UChar32 c) const2658 UBool Normalizer2Impl::isCanonSegmentStarter(UChar32 c) const {
2659     return getCanonValue(c)>=0;
2660 }
2661 
getCanonStartSet(UChar32 c,UnicodeSet & set) const2662 UBool Normalizer2Impl::getCanonStartSet(UChar32 c, UnicodeSet &set) const {
2663     int32_t canonValue=getCanonValue(c)&~CANON_NOT_SEGMENT_STARTER;
2664     if(canonValue==0) {
2665         return FALSE;
2666     }
2667     set.clear();
2668     int32_t value=canonValue&CANON_VALUE_MASK;
2669     if((canonValue&CANON_HAS_SET)!=0) {
2670         set.addAll(getCanonStartSet(value));
2671     } else if(value!=0) {
2672         set.add(value);
2673     }
2674     if((canonValue&CANON_HAS_COMPOSITIONS)!=0) {
2675         uint16_t norm16=getRawNorm16(c);
2676         if(norm16==JAMO_L) {
2677             UChar32 syllable=
2678                 (UChar32)(Hangul::HANGUL_BASE+(c-Hangul::JAMO_L_BASE)*Hangul::JAMO_VT_COUNT);
2679             set.add(syllable, syllable+Hangul::JAMO_VT_COUNT-1);
2680         } else {
2681             addComposites(getCompositionsList(norm16), set);
2682         }
2683     }
2684     return TRUE;
2685 }
2686 
2687 U_NAMESPACE_END
2688 
2689 // Normalizer2 data swapping ----------------------------------------------- ***
2690 
2691 U_NAMESPACE_USE
2692 
2693 U_CAPI int32_t U_EXPORT2
unorm2_swap(const UDataSwapper * ds,const void * inData,int32_t length,void * outData,UErrorCode * pErrorCode)2694 unorm2_swap(const UDataSwapper *ds,
2695             const void *inData, int32_t length, void *outData,
2696             UErrorCode *pErrorCode) {
2697     const UDataInfo *pInfo;
2698     int32_t headerSize;
2699 
2700     const uint8_t *inBytes;
2701     uint8_t *outBytes;
2702 
2703     const int32_t *inIndexes;
2704     int32_t indexes[Normalizer2Impl::IX_TOTAL_SIZE+1];
2705 
2706     int32_t i, offset, nextOffset, size;
2707 
2708     /* udata_swapDataHeader checks the arguments */
2709     headerSize=udata_swapDataHeader(ds, inData, length, outData, pErrorCode);
2710     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
2711         return 0;
2712     }
2713 
2714     /* check data format and format version */
2715     pInfo=(const UDataInfo *)((const char *)inData+4);
2716     uint8_t formatVersion0=pInfo->formatVersion[0];
2717     if(!(
2718         pInfo->dataFormat[0]==0x4e &&   /* dataFormat="Nrm2" */
2719         pInfo->dataFormat[1]==0x72 &&
2720         pInfo->dataFormat[2]==0x6d &&
2721         pInfo->dataFormat[3]==0x32 &&
2722         (1<=formatVersion0 && formatVersion0<=4)
2723     )) {
2724         udata_printError(ds, "unorm2_swap(): data format %02x.%02x.%02x.%02x (format version %02x) is not recognized as Normalizer2 data\n",
2725                          pInfo->dataFormat[0], pInfo->dataFormat[1],
2726                          pInfo->dataFormat[2], pInfo->dataFormat[3],
2727                          pInfo->formatVersion[0]);
2728         *pErrorCode=U_UNSUPPORTED_ERROR;
2729         return 0;
2730     }
2731 
2732     inBytes=(const uint8_t *)inData+headerSize;
2733     outBytes=(uint8_t *)outData+headerSize;
2734 
2735     inIndexes=(const int32_t *)inBytes;
2736     int32_t minIndexesLength;
2737     if(formatVersion0==1) {
2738         minIndexesLength=Normalizer2Impl::IX_MIN_MAYBE_YES+1;
2739     } else if(formatVersion0==2) {
2740         minIndexesLength=Normalizer2Impl::IX_MIN_YES_NO_MAPPINGS_ONLY+1;
2741     } else {
2742         minIndexesLength=Normalizer2Impl::IX_MIN_LCCC_CP+1;
2743     }
2744 
2745     if(length>=0) {
2746         length-=headerSize;
2747         if(length<minIndexesLength*4) {
2748             udata_printError(ds, "unorm2_swap(): too few bytes (%d after header) for Normalizer2 data\n",
2749                              length);
2750             *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
2751             return 0;
2752         }
2753     }
2754 
2755     /* read the first few indexes */
2756     for(i=0; i<UPRV_LENGTHOF(indexes); ++i) {
2757         indexes[i]=udata_readInt32(ds, inIndexes[i]);
2758     }
2759 
2760     /* get the total length of the data */
2761     size=indexes[Normalizer2Impl::IX_TOTAL_SIZE];
2762 
2763     if(length>=0) {
2764         if(length<size) {
2765             udata_printError(ds, "unorm2_swap(): too few bytes (%d after header) for all of Normalizer2 data\n",
2766                              length);
2767             *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
2768             return 0;
2769         }
2770 
2771         /* copy the data for inaccessible bytes */
2772         if(inBytes!=outBytes) {
2773             uprv_memcpy(outBytes, inBytes, size);
2774         }
2775 
2776         offset=0;
2777 
2778         /* swap the int32_t indexes[] */
2779         nextOffset=indexes[Normalizer2Impl::IX_NORM_TRIE_OFFSET];
2780         ds->swapArray32(ds, inBytes, nextOffset-offset, outBytes, pErrorCode);
2781         offset=nextOffset;
2782 
2783         /* swap the trie */
2784         nextOffset=indexes[Normalizer2Impl::IX_EXTRA_DATA_OFFSET];
2785         utrie_swapAnyVersion(ds, inBytes+offset, nextOffset-offset, outBytes+offset, pErrorCode);
2786         offset=nextOffset;
2787 
2788         /* swap the uint16_t extraData[] */
2789         nextOffset=indexes[Normalizer2Impl::IX_SMALL_FCD_OFFSET];
2790         ds->swapArray16(ds, inBytes+offset, nextOffset-offset, outBytes+offset, pErrorCode);
2791         offset=nextOffset;
2792 
2793         /* no need to swap the uint8_t smallFCD[] (new in formatVersion 2) */
2794         nextOffset=indexes[Normalizer2Impl::IX_SMALL_FCD_OFFSET+1];
2795         offset=nextOffset;
2796 
2797         U_ASSERT(offset==size);
2798     }
2799 
2800     return headerSize+size;
2801 }
2802 
2803 #endif  // !UCONFIG_NO_NORMALIZATION
2804