1 // 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ******************************************************************************* 5 * Copyright (C) 2012-2015, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ******************************************************************************* 8 * collationkeys.cpp 9 * 10 * created on: 2012sep02 11 * created by: Markus W. Scherer 12 */ 13 14 #include "unicode/utypes.h" 15 16 #if !UCONFIG_NO_COLLATION 17 18 #include "unicode/bytestream.h" 19 #include "collation.h" 20 #include "collationiterator.h" 21 #include "collationkeys.h" 22 #include "collationsettings.h" 23 #include "uassert.h" 24 25 U_NAMESPACE_BEGIN 26 27 SortKeyByteSink::~SortKeyByteSink() {} 28 29 void 30 SortKeyByteSink::Append(const char *bytes, int32_t n) { 31 if (n <= 0 || bytes == NULL) { 32 return; 33 } 34 if (ignore_ > 0) { 35 int32_t ignoreRest = ignore_ - n; 36 if (ignoreRest >= 0) { 37 ignore_ = ignoreRest; 38 return; 39 } else { 40 bytes += ignore_; 41 n = -ignoreRest; 42 ignore_ = 0; 43 } 44 } 45 int32_t length = appended_; 46 appended_ += n; 47 if ((buffer_ + length) == bytes) { 48 return; // the caller used GetAppendBuffer() and wrote the bytes already 49 } 50 int32_t available = capacity_ - length; 51 if (n <= available) { 52 uprv_memcpy(buffer_ + length, bytes, n); 53 } else { 54 AppendBeyondCapacity(bytes, n, length); 55 } 56 } 57 58 char * 59 SortKeyByteSink::GetAppendBuffer(int32_t min_capacity, 60 int32_t desired_capacity_hint, 61 char *scratch, 62 int32_t scratch_capacity, 63 int32_t *result_capacity) { 64 if (min_capacity < 1 || scratch_capacity < min_capacity) { 65 *result_capacity = 0; 66 return NULL; 67 } 68 if (ignore_ > 0) { 69 // Do not write ignored bytes right at the end of the buffer. 70 *result_capacity = scratch_capacity; 71 return scratch; 72 } 73 int32_t available = capacity_ - appended_; 74 if (available >= min_capacity) { 75 *result_capacity = available; 76 return buffer_ + appended_; 77 } else if (Resize(desired_capacity_hint, appended_)) { 78 *result_capacity = capacity_ - appended_; 79 return buffer_ + appended_; 80 } else { 81 *result_capacity = scratch_capacity; 82 return scratch; 83 } 84 } 85 86 namespace { 87 88 /** 89 * uint8_t byte buffer, similar to CharString but simpler. 90 */ 91 class SortKeyLevel : public UMemory { 92 public: 93 SortKeyLevel() : len(0), ok(TRUE) {} 94 ~SortKeyLevel() {} 95 96 /** @return FALSE if memory allocation failed */ 97 UBool isOk() const { return ok; } 98 UBool isEmpty() const { return len == 0; } 99 int32_t length() const { return len; } 100 const uint8_t *data() const { return buffer.getAlias(); } 101 uint8_t operator[](int32_t index) const { return buffer[index]; } 102 103 uint8_t *data() { return buffer.getAlias(); } 104 105 void appendByte(uint32_t b); 106 void appendWeight16(uint32_t w); 107 void appendWeight32(uint32_t w); 108 void appendReverseWeight16(uint32_t w); 109 110 /** Appends all but the last byte to the sink. The last byte should be the 01 terminator. */ 111 void appendTo(ByteSink &sink) const { 112 U_ASSERT(len > 0 && buffer[len - 1] == 1); 113 sink.Append(reinterpret_cast<const char *>(buffer.getAlias()), len - 1); 114 } 115 116 private: 117 MaybeStackArray<uint8_t, 40> buffer; 118 int32_t len; 119 UBool ok; 120 121 UBool ensureCapacity(int32_t appendCapacity); 122 123 SortKeyLevel(const SortKeyLevel &other); // forbid copying of this class 124 SortKeyLevel &operator=(const SortKeyLevel &other); // forbid copying of this class 125 }; 126 127 void SortKeyLevel::appendByte(uint32_t b) { 128 if(len < buffer.getCapacity() || ensureCapacity(1)) { 129 buffer[len++] = (uint8_t)b; 130 } 131 } 132 133 void 134 SortKeyLevel::appendWeight16(uint32_t w) { 135 U_ASSERT((w & 0xffff) != 0); 136 uint8_t b0 = (uint8_t)(w >> 8); 137 uint8_t b1 = (uint8_t)w; 138 int32_t appendLength = (b1 == 0) ? 1 : 2; 139 if((len + appendLength) <= buffer.getCapacity() || ensureCapacity(appendLength)) { 140 buffer[len++] = b0; 141 if(b1 != 0) { 142 buffer[len++] = b1; 143 } 144 } 145 } 146 147 void 148 SortKeyLevel::appendWeight32(uint32_t w) { 149 U_ASSERT(w != 0); 150 uint8_t bytes[4] = { (uint8_t)(w >> 24), (uint8_t)(w >> 16), (uint8_t)(w >> 8), (uint8_t)w }; 151 int32_t appendLength = (bytes[1] == 0) ? 1 : (bytes[2] == 0) ? 2 : (bytes[3] == 0) ? 3 : 4; 152 if((len + appendLength) <= buffer.getCapacity() || ensureCapacity(appendLength)) { 153 buffer[len++] = bytes[0]; 154 if(bytes[1] != 0) { 155 buffer[len++] = bytes[1]; 156 if(bytes[2] != 0) { 157 buffer[len++] = bytes[2]; 158 if(bytes[3] != 0) { 159 buffer[len++] = bytes[3]; 160 } 161 } 162 } 163 } 164 } 165 166 void 167 SortKeyLevel::appendReverseWeight16(uint32_t w) { 168 U_ASSERT((w & 0xffff) != 0); 169 uint8_t b0 = (uint8_t)(w >> 8); 170 uint8_t b1 = (uint8_t)w; 171 int32_t appendLength = (b1 == 0) ? 1 : 2; 172 if((len + appendLength) <= buffer.getCapacity() || ensureCapacity(appendLength)) { 173 if(b1 == 0) { 174 buffer[len++] = b0; 175 } else { 176 buffer[len] = b1; 177 buffer[len + 1] = b0; 178 len += 2; 179 } 180 } 181 } 182 183 UBool SortKeyLevel::ensureCapacity(int32_t appendCapacity) { 184 if(!ok) { 185 return FALSE; 186 } 187 int32_t newCapacity = 2 * buffer.getCapacity(); 188 int32_t altCapacity = len + 2 * appendCapacity; 189 if (newCapacity < altCapacity) { 190 newCapacity = altCapacity; 191 } 192 if (newCapacity < 200) { 193 newCapacity = 200; 194 } 195 if(buffer.resize(newCapacity, len)==NULL) { 196 return ok = FALSE; 197 } 198 return TRUE; 199 } 200 201 } // namespace 202 203 CollationKeys::LevelCallback::~LevelCallback() {} 204 205 UBool 206 CollationKeys::LevelCallback::needToWrite(Collation::Level /*level*/) { return TRUE; } 207 208 /** 209 * Map from collation strength (UColAttributeValue) 210 * to a mask of Collation::Level bits up to that strength, 211 * excluding the CASE_LEVEL which is independent of the strength, 212 * and excluding IDENTICAL_LEVEL which this function does not write. 213 */ 214 static const uint32_t levelMasks[UCOL_STRENGTH_LIMIT] = { 215 2, // UCOL_PRIMARY -> PRIMARY_LEVEL 216 6, // UCOL_SECONDARY -> up to SECONDARY_LEVEL 217 0x16, // UCOL_TERTIARY -> up to TERTIARY_LEVEL 218 0x36, // UCOL_QUATERNARY -> up to QUATERNARY_LEVEL 219 0, 0, 0, 0, 220 0, 0, 0, 0, 221 0, 0, 0, 222 0x36 // UCOL_IDENTICAL -> up to QUATERNARY_LEVEL 223 }; 224 225 void 226 CollationKeys::writeSortKeyUpToQuaternary(CollationIterator &iter, 227 const UBool *compressibleBytes, 228 const CollationSettings &settings, 229 SortKeyByteSink &sink, 230 Collation::Level minLevel, LevelCallback &callback, 231 UBool preflight, UErrorCode &errorCode) { 232 if(U_FAILURE(errorCode)) { return; } 233 234 int32_t options = settings.options; 235 // Set of levels to process and write. 236 uint32_t levels = levelMasks[CollationSettings::getStrength(options)]; 237 if((options & CollationSettings::CASE_LEVEL) != 0) { 238 levels |= Collation::CASE_LEVEL_FLAG; 239 } 240 // Minus the levels below minLevel. 241 levels &= ~(((uint32_t)1 << minLevel) - 1); 242 if(levels == 0) { return; } 243 244 uint32_t variableTop; 245 if((options & CollationSettings::ALTERNATE_MASK) == 0) { 246 variableTop = 0; 247 } else { 248 // +1 so that we can use "<" and primary ignorables test out early. 249 variableTop = settings.variableTop + 1; 250 } 251 252 uint32_t tertiaryMask = CollationSettings::getTertiaryMask(options); 253 254 SortKeyLevel cases; 255 SortKeyLevel secondaries; 256 SortKeyLevel tertiaries; 257 SortKeyLevel quaternaries; 258 259 uint32_t prevReorderedPrimary = 0; // 0==no compression 260 int32_t commonCases = 0; 261 int32_t commonSecondaries = 0; 262 int32_t commonTertiaries = 0; 263 int32_t commonQuaternaries = 0; 264 265 uint32_t prevSecondary = 0; 266 int32_t secSegmentStart = 0; 267 268 for(;;) { 269 // No need to keep all CEs in the buffer when we write a sort key. 270 iter.clearCEsIfNoneRemaining(); 271 int64_t ce = iter.nextCE(errorCode); 272 uint32_t p = (uint32_t)(ce >> 32); 273 if(p < variableTop && p > Collation::MERGE_SEPARATOR_PRIMARY) { 274 // Variable CE, shift it to quaternary level. 275 // Ignore all following primary ignorables, and shift further variable CEs. 276 if(commonQuaternaries != 0) { 277 --commonQuaternaries; 278 while(commonQuaternaries >= QUAT_COMMON_MAX_COUNT) { 279 quaternaries.appendByte(QUAT_COMMON_MIDDLE); 280 commonQuaternaries -= QUAT_COMMON_MAX_COUNT; 281 } 282 // Shifted primary weights are lower than the common weight. 283 quaternaries.appendByte(QUAT_COMMON_LOW + commonQuaternaries); 284 commonQuaternaries = 0; 285 } 286 do { 287 if((levels & Collation::QUATERNARY_LEVEL_FLAG) != 0) { 288 if(settings.hasReordering()) { 289 p = settings.reorder(p); 290 } 291 if((p >> 24) >= QUAT_SHIFTED_LIMIT_BYTE) { 292 // Prevent shifted primary lead bytes from 293 // overlapping with the common compression range. 294 quaternaries.appendByte(QUAT_SHIFTED_LIMIT_BYTE); 295 } 296 quaternaries.appendWeight32(p); 297 } 298 do { 299 ce = iter.nextCE(errorCode); 300 p = (uint32_t)(ce >> 32); 301 } while(p == 0); 302 } while(p < variableTop && p > Collation::MERGE_SEPARATOR_PRIMARY); 303 } 304 // ce could be primary ignorable, or NO_CE, or the merge separator, 305 // or a regular primary CE, but it is not variable. 306 // If ce==NO_CE, then write nothing for the primary level but 307 // terminate compression on all levels and then exit the loop. 308 if(p > Collation::NO_CE_PRIMARY && (levels & Collation::PRIMARY_LEVEL_FLAG) != 0) { 309 // Test the un-reordered primary for compressibility. 310 UBool isCompressible = compressibleBytes[p >> 24]; 311 if(settings.hasReordering()) { 312 p = settings.reorder(p); 313 } 314 uint32_t p1 = p >> 24; 315 if(!isCompressible || p1 != (prevReorderedPrimary >> 24)) { 316 if(prevReorderedPrimary != 0) { 317 if(p < prevReorderedPrimary) { 318 // No primary compression terminator 319 // at the end of the level or merged segment. 320 if(p1 > Collation::MERGE_SEPARATOR_BYTE) { 321 sink.Append(Collation::PRIMARY_COMPRESSION_LOW_BYTE); 322 } 323 } else { 324 sink.Append(Collation::PRIMARY_COMPRESSION_HIGH_BYTE); 325 } 326 } 327 sink.Append(p1); 328 if(isCompressible) { 329 prevReorderedPrimary = p; 330 } else { 331 prevReorderedPrimary = 0; 332 } 333 } 334 char p2 = (char)(p >> 16); 335 if(p2 != 0) { 336 char buffer[3] = { p2, (char)(p >> 8), (char)p }; 337 sink.Append(buffer, (buffer[1] == 0) ? 1 : (buffer[2] == 0) ? 2 : 3); 338 } 339 // Optimization for internalNextSortKeyPart(): 340 // When the primary level overflows we can stop because we need not 341 // calculate (preflight) the whole sort key length. 342 if(!preflight && sink.Overflowed()) { 343 if(U_SUCCESS(errorCode) && !sink.IsOk()) { 344 errorCode = U_MEMORY_ALLOCATION_ERROR; 345 } 346 return; 347 } 348 } 349 350 uint32_t lower32 = (uint32_t)ce; 351 if(lower32 == 0) { continue; } // completely ignorable, no secondary/case/tertiary/quaternary 352 353 if((levels & Collation::SECONDARY_LEVEL_FLAG) != 0) { 354 uint32_t s = lower32 >> 16; 355 if(s == 0) { 356 // secondary ignorable 357 } else if(s == Collation::COMMON_WEIGHT16 && 358 ((options & CollationSettings::BACKWARD_SECONDARY) == 0 || 359 p != Collation::MERGE_SEPARATOR_PRIMARY)) { 360 // s is a common secondary weight, and 361 // backwards-secondary is off or the ce is not the merge separator. 362 ++commonSecondaries; 363 } else if((options & CollationSettings::BACKWARD_SECONDARY) == 0) { 364 if(commonSecondaries != 0) { 365 --commonSecondaries; 366 while(commonSecondaries >= SEC_COMMON_MAX_COUNT) { 367 secondaries.appendByte(SEC_COMMON_MIDDLE); 368 commonSecondaries -= SEC_COMMON_MAX_COUNT; 369 } 370 uint32_t b; 371 if(s < Collation::COMMON_WEIGHT16) { 372 b = SEC_COMMON_LOW + commonSecondaries; 373 } else { 374 b = SEC_COMMON_HIGH - commonSecondaries; 375 } 376 secondaries.appendByte(b); 377 commonSecondaries = 0; 378 } 379 secondaries.appendWeight16(s); 380 } else { 381 if(commonSecondaries != 0) { 382 --commonSecondaries; 383 // Append reverse weights. The level will be re-reversed later. 384 int32_t remainder = commonSecondaries % SEC_COMMON_MAX_COUNT; 385 uint32_t b; 386 if(prevSecondary < Collation::COMMON_WEIGHT16) { 387 b = SEC_COMMON_LOW + remainder; 388 } else { 389 b = SEC_COMMON_HIGH - remainder; 390 } 391 secondaries.appendByte(b); 392 commonSecondaries -= remainder; 393 // commonSecondaries is now a multiple of SEC_COMMON_MAX_COUNT. 394 while(commonSecondaries > 0) { // same as >= SEC_COMMON_MAX_COUNT 395 secondaries.appendByte(SEC_COMMON_MIDDLE); 396 commonSecondaries -= SEC_COMMON_MAX_COUNT; 397 } 398 // commonSecondaries == 0 399 } 400 if(0 < p && p <= Collation::MERGE_SEPARATOR_PRIMARY) { 401 // The backwards secondary level compares secondary weights backwards 402 // within segments separated by the merge separator (U+FFFE). 403 uint8_t *secs = secondaries.data(); 404 int32_t last = secondaries.length() - 1; 405 if(secSegmentStart < last) { 406 uint8_t *p = secs + secSegmentStart; 407 uint8_t *q = secs + last; 408 do { 409 uint8_t b = *p; 410 *p++ = *q; 411 *q-- = b; 412 } while(p < q); 413 } 414 secondaries.appendByte(p == Collation::NO_CE_PRIMARY ? 415 Collation::LEVEL_SEPARATOR_BYTE : Collation::MERGE_SEPARATOR_BYTE); 416 prevSecondary = 0; 417 secSegmentStart = secondaries.length(); 418 } else { 419 secondaries.appendReverseWeight16(s); 420 prevSecondary = s; 421 } 422 } 423 } 424 425 if((levels & Collation::CASE_LEVEL_FLAG) != 0) { 426 if((CollationSettings::getStrength(options) == UCOL_PRIMARY) ? 427 p == 0 : lower32 <= 0xffff) { 428 // Primary+caseLevel: Ignore case level weights of primary ignorables. 429 // Otherwise: Ignore case level weights of secondary ignorables. 430 // For details see the comments in the CollationCompare class. 431 } else { 432 uint32_t c = (lower32 >> 8) & 0xff; // case bits & tertiary lead byte 433 U_ASSERT((c & 0xc0) != 0xc0); 434 if((c & 0xc0) == 0 && c > Collation::LEVEL_SEPARATOR_BYTE) { 435 ++commonCases; 436 } else { 437 if((options & CollationSettings::UPPER_FIRST) == 0) { 438 // lowerFirst: Compress common weights to nibbles 1..7..13, mixed=14, upper=15. 439 // If there are only common (=lowest) weights in the whole level, 440 // then we need not write anything. 441 // Level length differences are handled already on the next-higher level. 442 if(commonCases != 0 && 443 (c > Collation::LEVEL_SEPARATOR_BYTE || !cases.isEmpty())) { 444 --commonCases; 445 while(commonCases >= CASE_LOWER_FIRST_COMMON_MAX_COUNT) { 446 cases.appendByte(CASE_LOWER_FIRST_COMMON_MIDDLE << 4); 447 commonCases -= CASE_LOWER_FIRST_COMMON_MAX_COUNT; 448 } 449 uint32_t b; 450 if(c <= Collation::LEVEL_SEPARATOR_BYTE) { 451 b = CASE_LOWER_FIRST_COMMON_LOW + commonCases; 452 } else { 453 b = CASE_LOWER_FIRST_COMMON_HIGH - commonCases; 454 } 455 cases.appendByte(b << 4); 456 commonCases = 0; 457 } 458 if(c > Collation::LEVEL_SEPARATOR_BYTE) { 459 c = (CASE_LOWER_FIRST_COMMON_HIGH + (c >> 6)) << 4; // 14 or 15 460 } 461 } else { 462 // upperFirst: Compress common weights to nibbles 3..15, mixed=2, upper=1. 463 // The compressed common case weights only go up from the "low" value 464 // because with upperFirst the common weight is the highest one. 465 if(commonCases != 0) { 466 --commonCases; 467 while(commonCases >= CASE_UPPER_FIRST_COMMON_MAX_COUNT) { 468 cases.appendByte(CASE_UPPER_FIRST_COMMON_LOW << 4); 469 commonCases -= CASE_UPPER_FIRST_COMMON_MAX_COUNT; 470 } 471 cases.appendByte((CASE_UPPER_FIRST_COMMON_LOW + commonCases) << 4); 472 commonCases = 0; 473 } 474 if(c > Collation::LEVEL_SEPARATOR_BYTE) { 475 c = (CASE_UPPER_FIRST_COMMON_LOW - (c >> 6)) << 4; // 2 or 1 476 } 477 } 478 // c is a separator byte 01, 479 // or a left-shifted nibble 0x10, 0x20, ... 0xf0. 480 cases.appendByte(c); 481 } 482 } 483 } 484 485 if((levels & Collation::TERTIARY_LEVEL_FLAG) != 0) { 486 uint32_t t = lower32 & tertiaryMask; 487 U_ASSERT((lower32 & 0xc000) != 0xc000); 488 if(t == Collation::COMMON_WEIGHT16) { 489 ++commonTertiaries; 490 } else if((tertiaryMask & 0x8000) == 0) { 491 // Tertiary weights without case bits. 492 // Move lead bytes 06..3F to C6..FF for a large common-weight range. 493 if(commonTertiaries != 0) { 494 --commonTertiaries; 495 while(commonTertiaries >= TER_ONLY_COMMON_MAX_COUNT) { 496 tertiaries.appendByte(TER_ONLY_COMMON_MIDDLE); 497 commonTertiaries -= TER_ONLY_COMMON_MAX_COUNT; 498 } 499 uint32_t b; 500 if(t < Collation::COMMON_WEIGHT16) { 501 b = TER_ONLY_COMMON_LOW + commonTertiaries; 502 } else { 503 b = TER_ONLY_COMMON_HIGH - commonTertiaries; 504 } 505 tertiaries.appendByte(b); 506 commonTertiaries = 0; 507 } 508 if(t > Collation::COMMON_WEIGHT16) { t += 0xc000; } 509 tertiaries.appendWeight16(t); 510 } else if((options & CollationSettings::UPPER_FIRST) == 0) { 511 // Tertiary weights with caseFirst=lowerFirst. 512 // Move lead bytes 06..BF to 46..FF for the common-weight range. 513 if(commonTertiaries != 0) { 514 --commonTertiaries; 515 while(commonTertiaries >= TER_LOWER_FIRST_COMMON_MAX_COUNT) { 516 tertiaries.appendByte(TER_LOWER_FIRST_COMMON_MIDDLE); 517 commonTertiaries -= TER_LOWER_FIRST_COMMON_MAX_COUNT; 518 } 519 uint32_t b; 520 if(t < Collation::COMMON_WEIGHT16) { 521 b = TER_LOWER_FIRST_COMMON_LOW + commonTertiaries; 522 } else { 523 b = TER_LOWER_FIRST_COMMON_HIGH - commonTertiaries; 524 } 525 tertiaries.appendByte(b); 526 commonTertiaries = 0; 527 } 528 if(t > Collation::COMMON_WEIGHT16) { t += 0x4000; } 529 tertiaries.appendWeight16(t); 530 } else { 531 // Tertiary weights with caseFirst=upperFirst. 532 // Do not change the artificial uppercase weight of a tertiary CE (0.0.ut), 533 // to keep tertiary CEs well-formed. 534 // Their case+tertiary weights must be greater than those of 535 // primary and secondary CEs. 536 // 537 // Separator 01 -> 01 (unchanged) 538 // Lowercase 02..04 -> 82..84 (includes uncased) 539 // Common weight 05 -> 85..C5 (common-weight compression range) 540 // Lowercase 06..3F -> C6..FF 541 // Mixed case 42..7F -> 42..7F 542 // Uppercase 82..BF -> 02..3F 543 // Tertiary CE 86..BF -> C6..FF 544 if(t <= Collation::NO_CE_WEIGHT16) { 545 // Keep separators unchanged. 546 } else if(lower32 > 0xffff) { 547 // Invert case bits of primary & secondary CEs. 548 t ^= 0xc000; 549 if(t < (TER_UPPER_FIRST_COMMON_HIGH << 8)) { 550 t -= 0x4000; 551 } 552 } else { 553 // Keep uppercase bits of tertiary CEs. 554 U_ASSERT(0x8600 <= t && t <= 0xbfff); 555 t += 0x4000; 556 } 557 if(commonTertiaries != 0) { 558 --commonTertiaries; 559 while(commonTertiaries >= TER_UPPER_FIRST_COMMON_MAX_COUNT) { 560 tertiaries.appendByte(TER_UPPER_FIRST_COMMON_MIDDLE); 561 commonTertiaries -= TER_UPPER_FIRST_COMMON_MAX_COUNT; 562 } 563 uint32_t b; 564 if(t < (TER_UPPER_FIRST_COMMON_LOW << 8)) { 565 b = TER_UPPER_FIRST_COMMON_LOW + commonTertiaries; 566 } else { 567 b = TER_UPPER_FIRST_COMMON_HIGH - commonTertiaries; 568 } 569 tertiaries.appendByte(b); 570 commonTertiaries = 0; 571 } 572 tertiaries.appendWeight16(t); 573 } 574 } 575 576 if((levels & Collation::QUATERNARY_LEVEL_FLAG) != 0) { 577 uint32_t q = lower32 & 0xffff; 578 if((q & 0xc0) == 0 && q > Collation::NO_CE_WEIGHT16) { 579 ++commonQuaternaries; 580 } else if(q == Collation::NO_CE_WEIGHT16 && 581 (options & CollationSettings::ALTERNATE_MASK) == 0 && 582 quaternaries.isEmpty()) { 583 // If alternate=non-ignorable and there are only common quaternary weights, 584 // then we need not write anything. 585 // The only weights greater than the merge separator and less than the common weight 586 // are shifted primary weights, which are not generated for alternate=non-ignorable. 587 // There are also exactly as many quaternary weights as tertiary weights, 588 // so level length differences are handled already on tertiary level. 589 // Any above-common quaternary weight will compare greater regardless. 590 quaternaries.appendByte(Collation::LEVEL_SEPARATOR_BYTE); 591 } else { 592 if(q == Collation::NO_CE_WEIGHT16) { 593 q = Collation::LEVEL_SEPARATOR_BYTE; 594 } else { 595 q = 0xfc + ((q >> 6) & 3); 596 } 597 if(commonQuaternaries != 0) { 598 --commonQuaternaries; 599 while(commonQuaternaries >= QUAT_COMMON_MAX_COUNT) { 600 quaternaries.appendByte(QUAT_COMMON_MIDDLE); 601 commonQuaternaries -= QUAT_COMMON_MAX_COUNT; 602 } 603 uint32_t b; 604 if(q < QUAT_COMMON_LOW) { 605 b = QUAT_COMMON_LOW + commonQuaternaries; 606 } else { 607 b = QUAT_COMMON_HIGH - commonQuaternaries; 608 } 609 quaternaries.appendByte(b); 610 commonQuaternaries = 0; 611 } 612 quaternaries.appendByte(q); 613 } 614 } 615 616 if((lower32 >> 24) == Collation::LEVEL_SEPARATOR_BYTE) { break; } // ce == NO_CE 617 } 618 619 if(U_FAILURE(errorCode)) { return; } 620 621 // Append the beyond-primary levels. 622 UBool ok = TRUE; 623 if((levels & Collation::SECONDARY_LEVEL_FLAG) != 0) { 624 if(!callback.needToWrite(Collation::SECONDARY_LEVEL)) { return; } 625 ok &= secondaries.isOk(); 626 sink.Append(Collation::LEVEL_SEPARATOR_BYTE); 627 secondaries.appendTo(sink); 628 } 629 630 if((levels & Collation::CASE_LEVEL_FLAG) != 0) { 631 if(!callback.needToWrite(Collation::CASE_LEVEL)) { return; } 632 ok &= cases.isOk(); 633 sink.Append(Collation::LEVEL_SEPARATOR_BYTE); 634 // Write pairs of nibbles as bytes, except separator bytes as themselves. 635 int32_t length = cases.length() - 1; // Ignore the trailing NO_CE. 636 uint8_t b = 0; 637 for(int32_t i = 0; i < length; ++i) { 638 uint8_t c = (uint8_t)cases[i]; 639 U_ASSERT((c & 0xf) == 0 && c != 0); 640 if(b == 0) { 641 b = c; 642 } else { 643 sink.Append(b | (c >> 4)); 644 b = 0; 645 } 646 } 647 if(b != 0) { 648 sink.Append(b); 649 } 650 } 651 652 if((levels & Collation::TERTIARY_LEVEL_FLAG) != 0) { 653 if(!callback.needToWrite(Collation::TERTIARY_LEVEL)) { return; } 654 ok &= tertiaries.isOk(); 655 sink.Append(Collation::LEVEL_SEPARATOR_BYTE); 656 tertiaries.appendTo(sink); 657 } 658 659 if((levels & Collation::QUATERNARY_LEVEL_FLAG) != 0) { 660 if(!callback.needToWrite(Collation::QUATERNARY_LEVEL)) { return; } 661 ok &= quaternaries.isOk(); 662 sink.Append(Collation::LEVEL_SEPARATOR_BYTE); 663 quaternaries.appendTo(sink); 664 } 665 666 if(!ok || !sink.IsOk()) { 667 errorCode = U_MEMORY_ALLOCATION_ERROR; 668 } 669 } 670 671 U_NAMESPACE_END 672 673 #endif // !UCONFIG_NO_COLLATION 674