1 // Copyright (C) 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ******************************************************************************* 5 * 6 * Copyright (C) 2005-2016, International Business Machines 7 * Corporation and others. All Rights Reserved. 8 * 9 ******************************************************************************* 10 * file name: utext.cpp 11 * encoding: US-ASCII 12 * tab size: 8 (not used) 13 * indentation:4 14 * 15 * created on: 2005apr12 16 * created by: Markus W. Scherer 17 */ 18 19 #include "unicode/utypes.h" 20 #include "unicode/ustring.h" 21 #include "unicode/unistr.h" 22 #include "unicode/chariter.h" 23 #include "unicode/utext.h" 24 #include "unicode/utf.h" 25 #include "unicode/utf8.h" 26 #include "unicode/utf16.h" 27 #include "ustr_imp.h" 28 #include "cmemory.h" 29 #include "cstring.h" 30 #include "uassert.h" 31 #include "putilimp.h" 32 33 U_NAMESPACE_USE 34 35 #define I32_FLAG(bitIndex) ((int32_t)1<<(bitIndex)) 36 37 38 static UBool 39 utext_access(UText *ut, int64_t index, UBool forward) { 40 return ut->pFuncs->access(ut, index, forward); 41 } 42 43 44 45 U_CAPI UBool U_EXPORT2 46 utext_moveIndex32(UText *ut, int32_t delta) { 47 UChar32 c; 48 if (delta > 0) { 49 do { 50 if(ut->chunkOffset>=ut->chunkLength && !utext_access(ut, ut->chunkNativeLimit, TRUE)) { 51 return FALSE; 52 } 53 c = ut->chunkContents[ut->chunkOffset]; 54 if (U16_IS_SURROGATE(c)) { 55 c = utext_next32(ut); 56 if (c == U_SENTINEL) { 57 return FALSE; 58 } 59 } else { 60 ut->chunkOffset++; 61 } 62 } while(--delta>0); 63 64 } else if (delta<0) { 65 do { 66 if(ut->chunkOffset<=0 && !utext_access(ut, ut->chunkNativeStart, FALSE)) { 67 return FALSE; 68 } 69 c = ut->chunkContents[ut->chunkOffset-1]; 70 if (U16_IS_SURROGATE(c)) { 71 c = utext_previous32(ut); 72 if (c == U_SENTINEL) { 73 return FALSE; 74 } 75 } else { 76 ut->chunkOffset--; 77 } 78 } while(++delta<0); 79 } 80 81 return TRUE; 82 } 83 84 85 U_CAPI int64_t U_EXPORT2 86 utext_nativeLength(UText *ut) { 87 return ut->pFuncs->nativeLength(ut); 88 } 89 90 91 U_CAPI UBool U_EXPORT2 92 utext_isLengthExpensive(const UText *ut) { 93 UBool r = (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE)) != 0; 94 return r; 95 } 96 97 98 U_CAPI int64_t U_EXPORT2 99 utext_getNativeIndex(const UText *ut) { 100 if(ut->chunkOffset <= ut->nativeIndexingLimit) { 101 return ut->chunkNativeStart+ut->chunkOffset; 102 } else { 103 return ut->pFuncs->mapOffsetToNative(ut); 104 } 105 } 106 107 108 U_CAPI void U_EXPORT2 109 utext_setNativeIndex(UText *ut, int64_t index) { 110 if(index<ut->chunkNativeStart || index>=ut->chunkNativeLimit) { 111 // The desired position is outside of the current chunk. 112 // Access the new position. Assume a forward iteration from here, 113 // which will also be optimimum for a single random access. 114 // Reverse iterations may suffer slightly. 115 ut->pFuncs->access(ut, index, TRUE); 116 } else if((int32_t)(index - ut->chunkNativeStart) <= ut->nativeIndexingLimit) { 117 // utf-16 indexing. 118 ut->chunkOffset=(int32_t)(index-ut->chunkNativeStart); 119 } else { 120 ut->chunkOffset=ut->pFuncs->mapNativeIndexToUTF16(ut, index); 121 } 122 // The convention is that the index must always be on a code point boundary. 123 // Adjust the index position if it is in the middle of a surrogate pair. 124 if (ut->chunkOffset<ut->chunkLength) { 125 UChar c= ut->chunkContents[ut->chunkOffset]; 126 if (U16_IS_TRAIL(c)) { 127 if (ut->chunkOffset==0) { 128 ut->pFuncs->access(ut, ut->chunkNativeStart, FALSE); 129 } 130 if (ut->chunkOffset>0) { 131 UChar lead = ut->chunkContents[ut->chunkOffset-1]; 132 if (U16_IS_LEAD(lead)) { 133 ut->chunkOffset--; 134 } 135 } 136 } 137 } 138 } 139 140 141 142 U_CAPI int64_t U_EXPORT2 143 utext_getPreviousNativeIndex(UText *ut) { 144 // 145 // Fast-path the common case. 146 // Common means current position is not at the beginning of a chunk 147 // and the preceding character is not supplementary. 148 // 149 int32_t i = ut->chunkOffset - 1; 150 int64_t result; 151 if (i >= 0) { 152 UChar c = ut->chunkContents[i]; 153 if (U16_IS_TRAIL(c) == FALSE) { 154 if (i <= ut->nativeIndexingLimit) { 155 result = ut->chunkNativeStart + i; 156 } else { 157 ut->chunkOffset = i; 158 result = ut->pFuncs->mapOffsetToNative(ut); 159 ut->chunkOffset++; 160 } 161 return result; 162 } 163 } 164 165 // If at the start of text, simply return 0. 166 if (ut->chunkOffset==0 && ut->chunkNativeStart==0) { 167 return 0; 168 } 169 170 // Harder, less common cases. We are at a chunk boundary, or on a surrogate. 171 // Keep it simple, use other functions to handle the edges. 172 // 173 utext_previous32(ut); 174 result = UTEXT_GETNATIVEINDEX(ut); 175 utext_next32(ut); 176 return result; 177 } 178 179 180 // 181 // utext_current32. Get the UChar32 at the current position. 182 // UText iteration position is always on a code point boundary, 183 // never on the trail half of a surrogate pair. 184 // 185 U_CAPI UChar32 U_EXPORT2 186 utext_current32(UText *ut) { 187 UChar32 c; 188 if (ut->chunkOffset==ut->chunkLength) { 189 // Current position is just off the end of the chunk. 190 if (ut->pFuncs->access(ut, ut->chunkNativeLimit, TRUE) == FALSE) { 191 // Off the end of the text. 192 return U_SENTINEL; 193 } 194 } 195 196 c = ut->chunkContents[ut->chunkOffset]; 197 if (U16_IS_LEAD(c) == FALSE) { 198 // Normal, non-supplementary case. 199 return c; 200 } 201 202 // 203 // Possible supplementary char. 204 // 205 UChar32 trail = 0; 206 UChar32 supplementaryC = c; 207 if ((ut->chunkOffset+1) < ut->chunkLength) { 208 // The trail surrogate is in the same chunk. 209 trail = ut->chunkContents[ut->chunkOffset+1]; 210 } else { 211 // The trail surrogate is in a different chunk. 212 // Because we must maintain the iteration position, we need to switch forward 213 // into the new chunk, get the trail surrogate, then revert the chunk back to the 214 // original one. 215 // An edge case to be careful of: the entire text may end with an unpaired 216 // leading surrogate. The attempt to access the trail will fail, but 217 // the original position before the unpaired lead still needs to be restored. 218 int64_t nativePosition = ut->chunkNativeLimit; 219 int32_t originalOffset = ut->chunkOffset; 220 if (ut->pFuncs->access(ut, nativePosition, TRUE)) { 221 trail = ut->chunkContents[ut->chunkOffset]; 222 } 223 UBool r = ut->pFuncs->access(ut, nativePosition, FALSE); // reverse iteration flag loads preceding chunk 224 U_ASSERT(r==TRUE); 225 ut->chunkOffset = originalOffset; 226 if(!r) { 227 return U_SENTINEL; 228 } 229 } 230 231 if (U16_IS_TRAIL(trail)) { 232 supplementaryC = U16_GET_SUPPLEMENTARY(c, trail); 233 } 234 return supplementaryC; 235 236 } 237 238 239 U_CAPI UChar32 U_EXPORT2 240 utext_char32At(UText *ut, int64_t nativeIndex) { 241 UChar32 c = U_SENTINEL; 242 243 // Fast path the common case. 244 if (nativeIndex>=ut->chunkNativeStart && nativeIndex < ut->chunkNativeStart + ut->nativeIndexingLimit) { 245 ut->chunkOffset = (int32_t)(nativeIndex - ut->chunkNativeStart); 246 c = ut->chunkContents[ut->chunkOffset]; 247 if (U16_IS_SURROGATE(c) == FALSE) { 248 return c; 249 } 250 } 251 252 253 utext_setNativeIndex(ut, nativeIndex); 254 if (nativeIndex>=ut->chunkNativeStart && ut->chunkOffset<ut->chunkLength) { 255 c = ut->chunkContents[ut->chunkOffset]; 256 if (U16_IS_SURROGATE(c)) { 257 // For surrogates, let current32() deal with the complications 258 // of supplementaries that may span chunk boundaries. 259 c = utext_current32(ut); 260 } 261 } 262 return c; 263 } 264 265 266 U_CAPI UChar32 U_EXPORT2 267 utext_next32(UText *ut) { 268 UChar32 c; 269 270 if (ut->chunkOffset >= ut->chunkLength) { 271 if (ut->pFuncs->access(ut, ut->chunkNativeLimit, TRUE) == FALSE) { 272 return U_SENTINEL; 273 } 274 } 275 276 c = ut->chunkContents[ut->chunkOffset++]; 277 if (U16_IS_LEAD(c) == FALSE) { 278 // Normal case, not supplementary. 279 // (A trail surrogate seen here is just returned as is, as a surrogate value. 280 // It cannot be part of a pair.) 281 return c; 282 } 283 284 if (ut->chunkOffset >= ut->chunkLength) { 285 if (ut->pFuncs->access(ut, ut->chunkNativeLimit, TRUE) == FALSE) { 286 // c is an unpaired lead surrogate at the end of the text. 287 // return it as it is. 288 return c; 289 } 290 } 291 UChar32 trail = ut->chunkContents[ut->chunkOffset]; 292 if (U16_IS_TRAIL(trail) == FALSE) { 293 // c was an unpaired lead surrogate, not at the end of the text. 294 // return it as it is (unpaired). Iteration position is on the 295 // following character, possibly in the next chunk, where the 296 // trail surrogate would have been if it had existed. 297 return c; 298 } 299 300 UChar32 supplementary = U16_GET_SUPPLEMENTARY(c, trail); 301 ut->chunkOffset++; // move iteration position over the trail surrogate. 302 return supplementary; 303 } 304 305 306 U_CAPI UChar32 U_EXPORT2 307 utext_previous32(UText *ut) { 308 UChar32 c; 309 310 if (ut->chunkOffset <= 0) { 311 if (ut->pFuncs->access(ut, ut->chunkNativeStart, FALSE) == FALSE) { 312 return U_SENTINEL; 313 } 314 } 315 ut->chunkOffset--; 316 c = ut->chunkContents[ut->chunkOffset]; 317 if (U16_IS_TRAIL(c) == FALSE) { 318 // Normal case, not supplementary. 319 // (A lead surrogate seen here is just returned as is, as a surrogate value. 320 // It cannot be part of a pair.) 321 return c; 322 } 323 324 if (ut->chunkOffset <= 0) { 325 if (ut->pFuncs->access(ut, ut->chunkNativeStart, FALSE) == FALSE) { 326 // c is an unpaired trail surrogate at the start of the text. 327 // return it as it is. 328 return c; 329 } 330 } 331 332 UChar32 lead = ut->chunkContents[ut->chunkOffset-1]; 333 if (U16_IS_LEAD(lead) == FALSE) { 334 // c was an unpaired trail surrogate, not at the end of the text. 335 // return it as it is (unpaired). Iteration position is at c 336 return c; 337 } 338 339 UChar32 supplementary = U16_GET_SUPPLEMENTARY(lead, c); 340 ut->chunkOffset--; // move iteration position over the lead surrogate. 341 return supplementary; 342 } 343 344 345 346 U_CAPI UChar32 U_EXPORT2 347 utext_next32From(UText *ut, int64_t index) { 348 UChar32 c = U_SENTINEL; 349 350 if(index<ut->chunkNativeStart || index>=ut->chunkNativeLimit) { 351 // Desired position is outside of the current chunk. 352 if(!ut->pFuncs->access(ut, index, TRUE)) { 353 // no chunk available here 354 return U_SENTINEL; 355 } 356 } else if (index - ut->chunkNativeStart <= (int64_t)ut->nativeIndexingLimit) { 357 // Desired position is in chunk, with direct 1:1 native to UTF16 indexing 358 ut->chunkOffset = (int32_t)(index - ut->chunkNativeStart); 359 } else { 360 // Desired position is in chunk, with non-UTF16 indexing. 361 ut->chunkOffset = ut->pFuncs->mapNativeIndexToUTF16(ut, index); 362 } 363 364 c = ut->chunkContents[ut->chunkOffset++]; 365 if (U16_IS_SURROGATE(c)) { 366 // Surrogates. Many edge cases. Use other functions that already 367 // deal with the problems. 368 utext_setNativeIndex(ut, index); 369 c = utext_next32(ut); 370 } 371 return c; 372 } 373 374 375 U_CAPI UChar32 U_EXPORT2 376 utext_previous32From(UText *ut, int64_t index) { 377 // 378 // Return the character preceding the specified index. 379 // Leave the iteration position at the start of the character that was returned. 380 // 381 UChar32 cPrev; // The character preceding cCurr, which is what we will return. 382 383 // Address the chunk containg the position preceding the incoming index 384 // A tricky edge case: 385 // We try to test the requested native index against the chunkNativeStart to determine 386 // whether the character preceding the one at the index is in the current chunk. 387 // BUT, this test can fail with UTF-8 (or any other multibyte encoding), when the 388 // requested index is on something other than the first position of the first char. 389 // 390 if(index<=ut->chunkNativeStart || index>ut->chunkNativeLimit) { 391 // Requested native index is outside of the current chunk. 392 if(!ut->pFuncs->access(ut, index, FALSE)) { 393 // no chunk available here 394 return U_SENTINEL; 395 } 396 } else if(index - ut->chunkNativeStart <= (int64_t)ut->nativeIndexingLimit) { 397 // Direct UTF-16 indexing. 398 ut->chunkOffset = (int32_t)(index - ut->chunkNativeStart); 399 } else { 400 ut->chunkOffset=ut->pFuncs->mapNativeIndexToUTF16(ut, index); 401 if (ut->chunkOffset==0 && !ut->pFuncs->access(ut, index, FALSE)) { 402 // no chunk available here 403 return U_SENTINEL; 404 } 405 } 406 407 // 408 // Simple case with no surrogates. 409 // 410 ut->chunkOffset--; 411 cPrev = ut->chunkContents[ut->chunkOffset]; 412 413 if (U16_IS_SURROGATE(cPrev)) { 414 // Possible supplementary. Many edge cases. 415 // Let other functions do the heavy lifting. 416 utext_setNativeIndex(ut, index); 417 cPrev = utext_previous32(ut); 418 } 419 return cPrev; 420 } 421 422 423 U_CAPI int32_t U_EXPORT2 424 utext_extract(UText *ut, 425 int64_t start, int64_t limit, 426 UChar *dest, int32_t destCapacity, 427 UErrorCode *status) { 428 return ut->pFuncs->extract(ut, start, limit, dest, destCapacity, status); 429 } 430 431 432 433 U_CAPI UBool U_EXPORT2 434 utext_equals(const UText *a, const UText *b) { 435 if (a==NULL || b==NULL || 436 a->magic != UTEXT_MAGIC || 437 b->magic != UTEXT_MAGIC) { 438 // Null or invalid arguments don't compare equal to anything. 439 return FALSE; 440 } 441 442 if (a->pFuncs != b->pFuncs) { 443 // Different types of text providers. 444 return FALSE; 445 } 446 447 if (a->context != b->context) { 448 // Different sources (different strings) 449 return FALSE; 450 } 451 if (utext_getNativeIndex(a) != utext_getNativeIndex(b)) { 452 // Different current position in the string. 453 return FALSE; 454 } 455 456 return TRUE; 457 } 458 459 U_CAPI UBool U_EXPORT2 460 utext_isWritable(const UText *ut) 461 { 462 UBool b = (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_WRITABLE)) != 0; 463 return b; 464 } 465 466 467 U_CAPI void U_EXPORT2 468 utext_freeze(UText *ut) { 469 // Zero out the WRITABLE flag. 470 ut->providerProperties &= ~(I32_FLAG(UTEXT_PROVIDER_WRITABLE)); 471 } 472 473 474 U_CAPI UBool U_EXPORT2 475 utext_hasMetaData(const UText *ut) 476 { 477 UBool b = (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_HAS_META_DATA)) != 0; 478 return b; 479 } 480 481 482 483 U_CAPI int32_t U_EXPORT2 484 utext_replace(UText *ut, 485 int64_t nativeStart, int64_t nativeLimit, 486 const UChar *replacementText, int32_t replacementLength, 487 UErrorCode *status) 488 { 489 if (U_FAILURE(*status)) { 490 return 0; 491 } 492 if ((ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_WRITABLE)) == 0) { 493 *status = U_NO_WRITE_PERMISSION; 494 return 0; 495 } 496 int32_t i = ut->pFuncs->replace(ut, nativeStart, nativeLimit, replacementText, replacementLength, status); 497 return i; 498 } 499 500 U_CAPI void U_EXPORT2 501 utext_copy(UText *ut, 502 int64_t nativeStart, int64_t nativeLimit, 503 int64_t destIndex, 504 UBool move, 505 UErrorCode *status) 506 { 507 if (U_FAILURE(*status)) { 508 return; 509 } 510 if ((ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_WRITABLE)) == 0) { 511 *status = U_NO_WRITE_PERMISSION; 512 return; 513 } 514 ut->pFuncs->copy(ut, nativeStart, nativeLimit, destIndex, move, status); 515 } 516 517 518 519 U_CAPI UText * U_EXPORT2 520 utext_clone(UText *dest, const UText *src, UBool deep, UBool readOnly, UErrorCode *status) { 521 if (U_FAILURE(*status)) { 522 return dest; 523 } 524 UText *result = src->pFuncs->clone(dest, src, deep, status); 525 if (U_FAILURE(*status)) { 526 return result; 527 } 528 if (result == NULL) { 529 *status = U_MEMORY_ALLOCATION_ERROR; 530 return result; 531 } 532 if (readOnly) { 533 utext_freeze(result); 534 } 535 return result; 536 } 537 538 539 540 //------------------------------------------------------------------------------ 541 // 542 // UText common functions implementation 543 // 544 //------------------------------------------------------------------------------ 545 546 // 547 // UText.flags bit definitions 548 // 549 enum { 550 UTEXT_HEAP_ALLOCATED = 1, // 1 if ICU has allocated this UText struct on the heap. 551 // 0 if caller provided storage for the UText. 552 553 UTEXT_EXTRA_HEAP_ALLOCATED = 2, // 1 if ICU has allocated extra storage as a separate 554 // heap block. 555 // 0 if there is no separate allocation. Either no extra 556 // storage was requested, or it is appended to the end 557 // of the main UText storage. 558 559 UTEXT_OPEN = 4 // 1 if this UText is currently open 560 // 0 if this UText is not open. 561 }; 562 563 564 // 565 // Extended form of a UText. The purpose is to aid in computing the total size required 566 // when a provider asks for a UText to be allocated with extra storage. 567 568 struct ExtendedUText { 569 UText ut; 570 UAlignedMemory extension; 571 }; 572 573 static const UText emptyText = UTEXT_INITIALIZER; 574 575 U_CAPI UText * U_EXPORT2 576 utext_setup(UText *ut, int32_t extraSpace, UErrorCode *status) { 577 if (U_FAILURE(*status)) { 578 return ut; 579 } 580 581 if (ut == NULL) { 582 // We need to heap-allocate storage for the new UText 583 int32_t spaceRequired = sizeof(UText); 584 if (extraSpace > 0) { 585 spaceRequired = sizeof(ExtendedUText) + extraSpace - sizeof(UAlignedMemory); 586 } 587 ut = (UText *)uprv_malloc(spaceRequired); 588 if (ut == NULL) { 589 *status = U_MEMORY_ALLOCATION_ERROR; 590 return NULL; 591 } else { 592 *ut = emptyText; 593 ut->flags |= UTEXT_HEAP_ALLOCATED; 594 if (spaceRequired>0) { 595 ut->extraSize = extraSpace; 596 ut->pExtra = &((ExtendedUText *)ut)->extension; 597 } 598 } 599 } else { 600 // We have been supplied with an already existing UText. 601 // Verify that it really appears to be a UText. 602 if (ut->magic != UTEXT_MAGIC) { 603 *status = U_ILLEGAL_ARGUMENT_ERROR; 604 return ut; 605 } 606 // If the ut is already open and there's a provider supplied close 607 // function, call it. 608 if ((ut->flags & UTEXT_OPEN) && ut->pFuncs->close != NULL) { 609 ut->pFuncs->close(ut); 610 } 611 ut->flags &= ~UTEXT_OPEN; 612 613 // If extra space was requested by our caller, check whether 614 // sufficient already exists, and allocate new if needed. 615 if (extraSpace > ut->extraSize) { 616 // Need more space. If there is existing separately allocated space, 617 // delete it first, then allocate new space. 618 if (ut->flags & UTEXT_EXTRA_HEAP_ALLOCATED) { 619 uprv_free(ut->pExtra); 620 ut->extraSize = 0; 621 } 622 ut->pExtra = uprv_malloc(extraSpace); 623 if (ut->pExtra == NULL) { 624 *status = U_MEMORY_ALLOCATION_ERROR; 625 } else { 626 ut->extraSize = extraSpace; 627 ut->flags |= UTEXT_EXTRA_HEAP_ALLOCATED; 628 } 629 } 630 } 631 if (U_SUCCESS(*status)) { 632 ut->flags |= UTEXT_OPEN; 633 634 // Initialize all remaining fields of the UText. 635 // 636 ut->context = NULL; 637 ut->chunkContents = NULL; 638 ut->p = NULL; 639 ut->q = NULL; 640 ut->r = NULL; 641 ut->a = 0; 642 ut->b = 0; 643 ut->c = 0; 644 ut->chunkOffset = 0; 645 ut->chunkLength = 0; 646 ut->chunkNativeStart = 0; 647 ut->chunkNativeLimit = 0; 648 ut->nativeIndexingLimit = 0; 649 ut->providerProperties = 0; 650 ut->privA = 0; 651 ut->privB = 0; 652 ut->privC = 0; 653 ut->privP = NULL; 654 if (ut->pExtra!=NULL && ut->extraSize>0) 655 uprv_memset(ut->pExtra, 0, ut->extraSize); 656 657 } 658 return ut; 659 } 660 661 662 U_CAPI UText * U_EXPORT2 663 utext_close(UText *ut) { 664 if (ut==NULL || 665 ut->magic != UTEXT_MAGIC || 666 (ut->flags & UTEXT_OPEN) == 0) 667 { 668 // The supplied ut is not an open UText. 669 // Do nothing. 670 return ut; 671 } 672 673 // If the provider gave us a close function, call it now. 674 // This will clean up anything allocated specifically by the provider. 675 if (ut->pFuncs->close != NULL) { 676 ut->pFuncs->close(ut); 677 } 678 ut->flags &= ~UTEXT_OPEN; 679 680 // If we (the framework) allocated the UText or subsidiary storage, 681 // delete it. 682 if (ut->flags & UTEXT_EXTRA_HEAP_ALLOCATED) { 683 uprv_free(ut->pExtra); 684 ut->pExtra = NULL; 685 ut->flags &= ~UTEXT_EXTRA_HEAP_ALLOCATED; 686 ut->extraSize = 0; 687 } 688 689 // Zero out function table of the closed UText. This is a defensive move, 690 // inteded to cause applications that inadvertantly use a closed 691 // utext to crash with null pointer errors. 692 ut->pFuncs = NULL; 693 694 if (ut->flags & UTEXT_HEAP_ALLOCATED) { 695 // This UText was allocated by UText setup. We need to free it. 696 // Clear magic, so we can detect if the user messes up and immediately 697 // tries to reopen another UText using the deleted storage. 698 ut->magic = 0; 699 uprv_free(ut); 700 ut = NULL; 701 } 702 return ut; 703 } 704 705 706 707 708 // 709 // invalidateChunk Reset a chunk to have no contents, so that the next call 710 // to access will cause new data to load. 711 // This is needed when copy/move/replace operate directly on the 712 // backing text, potentially putting it out of sync with the 713 // contents in the chunk. 714 // 715 static void 716 invalidateChunk(UText *ut) { 717 ut->chunkLength = 0; 718 ut->chunkNativeLimit = 0; 719 ut->chunkNativeStart = 0; 720 ut->chunkOffset = 0; 721 ut->nativeIndexingLimit = 0; 722 } 723 724 // 725 // pinIndex Do range pinning on a native index parameter. 726 // 64 bit pinning is done in place. 727 // 32 bit truncated result is returned as a convenience for 728 // use in providers that don't need 64 bits. 729 static int32_t 730 pinIndex(int64_t &index, int64_t limit) { 731 if (index<0) { 732 index = 0; 733 } else if (index > limit) { 734 index = limit; 735 } 736 return (int32_t)index; 737 } 738 739 740 U_CDECL_BEGIN 741 742 // 743 // Pointer relocation function, 744 // a utility used by shallow clone. 745 // Adjust a pointer that refers to something within one UText (the source) 746 // to refer to the same relative offset within a another UText (the target) 747 // 748 static void adjustPointer(UText *dest, const void **destPtr, const UText *src) { 749 // convert all pointers to (char *) so that byte address arithmetic will work. 750 char *dptr = (char *)*destPtr; 751 char *dUText = (char *)dest; 752 char *sUText = (char *)src; 753 754 if (dptr >= (char *)src->pExtra && dptr < ((char*)src->pExtra)+src->extraSize) { 755 // target ptr was to something within the src UText's pExtra storage. 756 // relocate it into the target UText's pExtra region. 757 *destPtr = ((char *)dest->pExtra) + (dptr - (char *)src->pExtra); 758 } else if (dptr>=sUText && dptr < sUText+src->sizeOfStruct) { 759 // target ptr was pointing to somewhere within the source UText itself. 760 // Move it to the same offset within the target UText. 761 *destPtr = dUText + (dptr-sUText); 762 } 763 } 764 765 766 // 767 // Clone. This is a generic copy-the-utext-by-value clone function that can be 768 // used as-is with some utext types, and as a helper by other clones. 769 // 770 static UText * U_CALLCONV 771 shallowTextClone(UText * dest, const UText * src, UErrorCode * status) { 772 if (U_FAILURE(*status)) { 773 return NULL; 774 } 775 int32_t srcExtraSize = src->extraSize; 776 777 // 778 // Use the generic text_setup to allocate storage if required. 779 // 780 dest = utext_setup(dest, srcExtraSize, status); 781 if (U_FAILURE(*status)) { 782 return dest; 783 } 784 785 // 786 // flags (how the UText was allocated) and the pointer to the 787 // extra storage must retain the values in the cloned utext that 788 // were set up by utext_setup. Save them separately before 789 // copying the whole struct. 790 // 791 void *destExtra = dest->pExtra; 792 int32_t flags = dest->flags; 793 794 795 // 796 // Copy the whole UText struct by value. 797 // Any "Extra" storage is copied also. 798 // 799 int sizeToCopy = src->sizeOfStruct; 800 if (sizeToCopy > dest->sizeOfStruct) { 801 sizeToCopy = dest->sizeOfStruct; 802 } 803 uprv_memcpy(dest, src, sizeToCopy); 804 dest->pExtra = destExtra; 805 dest->flags = flags; 806 if (srcExtraSize > 0) { 807 uprv_memcpy(dest->pExtra, src->pExtra, srcExtraSize); 808 } 809 810 // 811 // Relocate any pointers in the target that refer to the UText itself 812 // to point to the cloned copy rather than the original source. 813 // 814 adjustPointer(dest, &dest->context, src); 815 adjustPointer(dest, &dest->p, src); 816 adjustPointer(dest, &dest->q, src); 817 adjustPointer(dest, &dest->r, src); 818 adjustPointer(dest, (const void **)&dest->chunkContents, src); 819 820 // The newly shallow-cloned UText does _not_ own the underlying storage for the text. 821 // (The source for the clone may or may not have owned the text.) 822 823 dest->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT); 824 825 return dest; 826 } 827 828 829 U_CDECL_END 830 831 832 833 //------------------------------------------------------------------------------ 834 // 835 // UText implementation for UTF-8 char * strings (read-only) 836 // Limitation: string length must be <= 0x7fffffff in length. 837 // (length must for in an int32_t variable) 838 // 839 // Use of UText data members: 840 // context pointer to UTF-8 string 841 // utext.b is the input string length (bytes). 842 // utext.c Length scanned so far in string 843 // (for optimizing finding length of zero terminated strings.) 844 // utext.p pointer to the current buffer 845 // utext.q pointer to the other buffer. 846 // 847 //------------------------------------------------------------------------------ 848 849 // Chunk size. 850 // Must be less than 85, because of byte mapping from UChar indexes to native indexes. 851 // Worst case is three native bytes to one UChar. (Supplemenaries are 4 native bytes 852 // to two UChars.) 853 // 854 enum { UTF8_TEXT_CHUNK_SIZE=32 }; 855 856 // 857 // UTF8Buf Two of these structs will be set up in the UText's extra allocated space. 858 // Each contains the UChar chunk buffer, the to and from native maps, and 859 // header info. 860 // 861 // because backwards iteration fills the buffers starting at the end and 862 // working towards the front, the filled part of the buffers may not begin 863 // at the start of the available storage for the buffers. 864 // 865 // Buffer size is one bigger than the specified UTF8_TEXT_CHUNK_SIZE to allow for 866 // the last character added being a supplementary, and thus requiring a surrogate 867 // pair. Doing this is simpler than checking for the edge case. 868 // 869 870 struct UTF8Buf { 871 int32_t bufNativeStart; // Native index of first char in UChar buf 872 int32_t bufNativeLimit; // Native index following last char in buf. 873 int32_t bufStartIdx; // First filled position in buf. 874 int32_t bufLimitIdx; // Limit of filled range in buf. 875 int32_t bufNILimit; // Limit of native indexing part of buf 876 int32_t toUCharsMapStart; // Native index corresponding to 877 // mapToUChars[0]. 878 // Set to bufNativeStart when filling forwards. 879 // Set to computed value when filling backwards. 880 881 UChar buf[UTF8_TEXT_CHUNK_SIZE+4]; // The UChar buffer. Requires one extra position beyond the 882 // the chunk size, to allow for surrogate at the end. 883 // Length must be identical to mapToNative array, below, 884 // because of the way indexing works when the array is 885 // filled backwards during a reverse iteration. Thus, 886 // the additional extra size. 887 uint8_t mapToNative[UTF8_TEXT_CHUNK_SIZE+4]; // map UChar index in buf to 888 // native offset from bufNativeStart. 889 // Requires two extra slots, 890 // one for a supplementary starting in the last normal position, 891 // and one for an entry for the buffer limit position. 892 uint8_t mapToUChars[UTF8_TEXT_CHUNK_SIZE*3+6]; // Map native offset from bufNativeStart to 893 // correspoding offset in filled part of buf. 894 int32_t align; 895 }; 896 897 U_CDECL_BEGIN 898 899 // 900 // utf8TextLength 901 // 902 // Get the length of the string. If we don't already know it, 903 // we'll need to scan for the trailing nul. 904 // 905 static int64_t U_CALLCONV 906 utf8TextLength(UText *ut) { 907 if (ut->b < 0) { 908 // Zero terminated string, and we haven't scanned to the end yet. 909 // Scan it now. 910 const char *r = (const char *)ut->context + ut->c; 911 while (*r != 0) { 912 r++; 913 } 914 if ((r - (const char *)ut->context) < 0x7fffffff) { 915 ut->b = (int32_t)(r - (const char *)ut->context); 916 } else { 917 // Actual string was bigger (more than 2 gig) than we 918 // can handle. Clip it to 2 GB. 919 ut->b = 0x7fffffff; 920 } 921 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 922 } 923 return ut->b; 924 } 925 926 927 928 929 930 931 static UBool U_CALLCONV 932 utf8TextAccess(UText *ut, int64_t index, UBool forward) { 933 // 934 // Apologies to those who are allergic to goto statements. 935 // Consider each goto to a labelled block to be the equivalent of 936 // call the named block as if it were a function(); 937 // return; 938 // 939 const uint8_t *s8=(const uint8_t *)ut->context; 940 UTF8Buf *u8b = NULL; 941 int32_t length = ut->b; // Length of original utf-8 942 int32_t ix= (int32_t)index; // Requested index, trimmed to 32 bits. 943 int32_t mapIndex = 0; 944 if (index<0) { 945 ix=0; 946 } else if (index > 0x7fffffff) { 947 // Strings with 64 bit lengths not supported by this UTF-8 provider. 948 ix = 0x7fffffff; 949 } 950 951 // Pin requested index to the string length. 952 if (ix>length) { 953 if (length>=0) { 954 ix=length; 955 } else if (ix>=ut->c) { 956 // Zero terminated string, and requested index is beyond 957 // the region that has already been scanned. 958 // Scan up to either the end of the string or to the 959 // requested position, whichever comes first. 960 while (ut->c<ix && s8[ut->c]!=0) { 961 ut->c++; 962 } 963 // TODO: support for null terminated string length > 32 bits. 964 if (s8[ut->c] == 0) { 965 // We just found the actual length of the string. 966 // Trim the requested index back to that. 967 ix = ut->c; 968 ut->b = ut->c; 969 length = ut->c; 970 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 971 } 972 } 973 } 974 975 // 976 // Dispatch to the appropriate action for a forward iteration request. 977 // 978 if (forward) { 979 if (ix==ut->chunkNativeLimit) { 980 // Check for normal sequential iteration cases first. 981 if (ix==length) { 982 // Just reached end of string 983 // Don't swap buffers, but do set the 984 // current buffer position. 985 ut->chunkOffset = ut->chunkLength; 986 return FALSE; 987 } else { 988 // End of current buffer. 989 // check whether other buffer already has what we need. 990 UTF8Buf *altB = (UTF8Buf *)ut->q; 991 if (ix>=altB->bufNativeStart && ix<altB->bufNativeLimit) { 992 goto swapBuffers; 993 } 994 } 995 } 996 997 // A random access. Desired index could be in either or niether buf. 998 // For optimizing the order of testing, first check for the index 999 // being in the other buffer. This will be the case for uses that 1000 // move back and forth over a fairly limited range 1001 { 1002 u8b = (UTF8Buf *)ut->q; // the alternate buffer 1003 if (ix>=u8b->bufNativeStart && ix<u8b->bufNativeLimit) { 1004 // Requested index is in the other buffer. 1005 goto swapBuffers; 1006 } 1007 if (ix == length) { 1008 // Requested index is end-of-string. 1009 // (this is the case of randomly seeking to the end. 1010 // The case of iterating off the end is handled earlier.) 1011 if (ix == ut->chunkNativeLimit) { 1012 // Current buffer extends up to the end of the string. 1013 // Leave it as the current buffer. 1014 ut->chunkOffset = ut->chunkLength; 1015 return FALSE; 1016 } 1017 if (ix == u8b->bufNativeLimit) { 1018 // Alternate buffer extends to the end of string. 1019 // Swap it in as the current buffer. 1020 goto swapBuffersAndFail; 1021 } 1022 1023 // Neither existing buffer extends to the end of the string. 1024 goto makeStubBuffer; 1025 } 1026 1027 if (ix<ut->chunkNativeStart || ix>=ut->chunkNativeLimit) { 1028 // Requested index is in neither buffer. 1029 goto fillForward; 1030 } 1031 1032 // Requested index is in this buffer. 1033 u8b = (UTF8Buf *)ut->p; // the current buffer 1034 mapIndex = ix - u8b->toUCharsMapStart; 1035 ut->chunkOffset = u8b->mapToUChars[mapIndex] - u8b->bufStartIdx; 1036 return TRUE; 1037 1038 } 1039 } 1040 1041 1042 // 1043 // Dispatch to the appropriate action for a 1044 // Backwards Diretion iteration request. 1045 // 1046 if (ix==ut->chunkNativeStart) { 1047 // Check for normal sequential iteration cases first. 1048 if (ix==0) { 1049 // Just reached the start of string 1050 // Don't swap buffers, but do set the 1051 // current buffer position. 1052 ut->chunkOffset = 0; 1053 return FALSE; 1054 } else { 1055 // Start of current buffer. 1056 // check whether other buffer already has what we need. 1057 UTF8Buf *altB = (UTF8Buf *)ut->q; 1058 if (ix>altB->bufNativeStart && ix<=altB->bufNativeLimit) { 1059 goto swapBuffers; 1060 } 1061 } 1062 } 1063 1064 // A random access. Desired index could be in either or niether buf. 1065 // For optimizing the order of testing, 1066 // Most likely case: in the other buffer. 1067 // Second most likely: in neither buffer. 1068 // Unlikely, but must work: in the current buffer. 1069 u8b = (UTF8Buf *)ut->q; // the alternate buffer 1070 if (ix>u8b->bufNativeStart && ix<=u8b->bufNativeLimit) { 1071 // Requested index is in the other buffer. 1072 goto swapBuffers; 1073 } 1074 // Requested index is start-of-string. 1075 // (this is the case of randomly seeking to the start. 1076 // The case of iterating off the start is handled earlier.) 1077 if (ix==0) { 1078 if (u8b->bufNativeStart==0) { 1079 // Alternate buffer contains the data for the start string. 1080 // Make it be the current buffer. 1081 goto swapBuffersAndFail; 1082 } else { 1083 // Request for data before the start of string, 1084 // neither buffer is usable. 1085 // set up a zero-length buffer. 1086 goto makeStubBuffer; 1087 } 1088 } 1089 1090 if (ix<=ut->chunkNativeStart || ix>ut->chunkNativeLimit) { 1091 // Requested index is in neither buffer. 1092 goto fillReverse; 1093 } 1094 1095 // Requested index is in this buffer. 1096 // Set the utf16 buffer index. 1097 u8b = (UTF8Buf *)ut->p; 1098 mapIndex = ix - u8b->toUCharsMapStart; 1099 ut->chunkOffset = u8b->mapToUChars[mapIndex] - u8b->bufStartIdx; 1100 if (ut->chunkOffset==0) { 1101 // This occurs when the first character in the text is 1102 // a multi-byte UTF-8 char, and the requested index is to 1103 // one of the trailing bytes. Because there is no preceding , 1104 // character, this access fails. We can't pick up on the 1105 // situation sooner because the requested index is not zero. 1106 return FALSE; 1107 } else { 1108 return TRUE; 1109 } 1110 1111 1112 1113 swapBuffers: 1114 // The alternate buffer (ut->q) has the string data that was requested. 1115 // Swap the primary and alternate buffers, and set the 1116 // chunk index into the new primary buffer. 1117 { 1118 u8b = (UTF8Buf *)ut->q; 1119 ut->q = ut->p; 1120 ut->p = u8b; 1121 ut->chunkContents = &u8b->buf[u8b->bufStartIdx]; 1122 ut->chunkLength = u8b->bufLimitIdx - u8b->bufStartIdx; 1123 ut->chunkNativeStart = u8b->bufNativeStart; 1124 ut->chunkNativeLimit = u8b->bufNativeLimit; 1125 ut->nativeIndexingLimit = u8b->bufNILimit; 1126 1127 // Index into the (now current) chunk 1128 // Use the map to set the chunk index. It's more trouble than it's worth 1129 // to check whether native indexing can be used. 1130 U_ASSERT(ix>=u8b->bufNativeStart); 1131 U_ASSERT(ix<=u8b->bufNativeLimit); 1132 mapIndex = ix - u8b->toUCharsMapStart; 1133 U_ASSERT(mapIndex>=0); 1134 U_ASSERT(mapIndex<(int32_t)sizeof(u8b->mapToUChars)); 1135 ut->chunkOffset = u8b->mapToUChars[mapIndex] - u8b->bufStartIdx; 1136 1137 return TRUE; 1138 } 1139 1140 1141 swapBuffersAndFail: 1142 // We got a request for either the start or end of the string, 1143 // with iteration continuing in the out-of-bounds direction. 1144 // The alternate buffer already contains the data up to the 1145 // start/end. 1146 // Swap the buffers, then return failure, indicating that we couldn't 1147 // make things correct for continuing the iteration in the requested 1148 // direction. The position & buffer are correct should the 1149 // user decide to iterate in the opposite direction. 1150 u8b = (UTF8Buf *)ut->q; 1151 ut->q = ut->p; 1152 ut->p = u8b; 1153 ut->chunkContents = &u8b->buf[u8b->bufStartIdx]; 1154 ut->chunkLength = u8b->bufLimitIdx - u8b->bufStartIdx; 1155 ut->chunkNativeStart = u8b->bufNativeStart; 1156 ut->chunkNativeLimit = u8b->bufNativeLimit; 1157 ut->nativeIndexingLimit = u8b->bufNILimit; 1158 1159 // Index into the (now current) chunk 1160 // For this function (swapBuffersAndFail), the requested index 1161 // will always be at either the start or end of the chunk. 1162 if (ix==u8b->bufNativeLimit) { 1163 ut->chunkOffset = ut->chunkLength; 1164 } else { 1165 ut->chunkOffset = 0; 1166 U_ASSERT(ix == u8b->bufNativeStart); 1167 } 1168 return FALSE; 1169 1170 makeStubBuffer: 1171 // The user has done a seek/access past the start or end 1172 // of the string. Rather than loading data that is likely 1173 // to never be used, just set up a zero-length buffer at 1174 // the position. 1175 u8b = (UTF8Buf *)ut->q; 1176 u8b->bufNativeStart = ix; 1177 u8b->bufNativeLimit = ix; 1178 u8b->bufStartIdx = 0; 1179 u8b->bufLimitIdx = 0; 1180 u8b->bufNILimit = 0; 1181 u8b->toUCharsMapStart = ix; 1182 u8b->mapToNative[0] = 0; 1183 u8b->mapToUChars[0] = 0; 1184 goto swapBuffersAndFail; 1185 1186 1187 1188 fillForward: 1189 { 1190 // Move the incoming index to a code point boundary. 1191 U8_SET_CP_START(s8, 0, ix); 1192 1193 // Swap the UText buffers. 1194 // We want to fill what was previously the alternate buffer, 1195 // and make what was the current buffer be the new alternate. 1196 UTF8Buf *u8b = (UTF8Buf *)ut->q; 1197 ut->q = ut->p; 1198 ut->p = u8b; 1199 1200 int32_t strLen = ut->b; 1201 UBool nulTerminated = FALSE; 1202 if (strLen < 0) { 1203 strLen = 0x7fffffff; 1204 nulTerminated = TRUE; 1205 } 1206 1207 UChar *buf = u8b->buf; 1208 uint8_t *mapToNative = u8b->mapToNative; 1209 uint8_t *mapToUChars = u8b->mapToUChars; 1210 int32_t destIx = 0; 1211 int32_t srcIx = ix; 1212 UBool seenNonAscii = FALSE; 1213 UChar32 c = 0; 1214 1215 // Fill the chunk buffer and mapping arrays. 1216 while (destIx<UTF8_TEXT_CHUNK_SIZE) { 1217 c = s8[srcIx]; 1218 if (c>0 && c<0x80) { 1219 // Special case ASCII range for speed. 1220 // zero is excluded to simplify bounds checking. 1221 buf[destIx] = (UChar)c; 1222 mapToNative[destIx] = (uint8_t)(srcIx - ix); 1223 mapToUChars[srcIx-ix] = (uint8_t)destIx; 1224 srcIx++; 1225 destIx++; 1226 } else { 1227 // General case, handle everything. 1228 if (seenNonAscii == FALSE) { 1229 seenNonAscii = TRUE; 1230 u8b->bufNILimit = destIx; 1231 } 1232 1233 int32_t cIx = srcIx; 1234 int32_t dIx = destIx; 1235 int32_t dIxSaved = destIx; 1236 U8_NEXT_OR_FFFD(s8, srcIx, strLen, c); 1237 if (c==0 && nulTerminated) { 1238 srcIx--; 1239 break; 1240 } 1241 1242 U16_APPEND_UNSAFE(buf, destIx, c); 1243 do { 1244 mapToNative[dIx++] = (uint8_t)(cIx - ix); 1245 } while (dIx < destIx); 1246 1247 do { 1248 mapToUChars[cIx++ - ix] = (uint8_t)dIxSaved; 1249 } while (cIx < srcIx); 1250 } 1251 if (srcIx>=strLen) { 1252 break; 1253 } 1254 1255 } 1256 1257 // store Native <--> Chunk Map entries for the end of the buffer. 1258 // There is no actual character here, but the index position is valid. 1259 mapToNative[destIx] = (uint8_t)(srcIx - ix); 1260 mapToUChars[srcIx - ix] = (uint8_t)destIx; 1261 1262 // fill in Buffer descriptor 1263 u8b->bufNativeStart = ix; 1264 u8b->bufNativeLimit = srcIx; 1265 u8b->bufStartIdx = 0; 1266 u8b->bufLimitIdx = destIx; 1267 if (seenNonAscii == FALSE) { 1268 u8b->bufNILimit = destIx; 1269 } 1270 u8b->toUCharsMapStart = u8b->bufNativeStart; 1271 1272 // Set UText chunk to refer to this buffer. 1273 ut->chunkContents = buf; 1274 ut->chunkOffset = 0; 1275 ut->chunkLength = u8b->bufLimitIdx; 1276 ut->chunkNativeStart = u8b->bufNativeStart; 1277 ut->chunkNativeLimit = u8b->bufNativeLimit; 1278 ut->nativeIndexingLimit = u8b->bufNILimit; 1279 1280 // For zero terminated strings, keep track of the maximum point 1281 // scanned so far. 1282 if (nulTerminated && srcIx>ut->c) { 1283 ut->c = srcIx; 1284 if (c==0) { 1285 // We scanned to the end. 1286 // Remember the actual length. 1287 ut->b = srcIx; 1288 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 1289 } 1290 } 1291 return TRUE; 1292 } 1293 1294 1295 fillReverse: 1296 { 1297 // Move the incoming index to a code point boundary. 1298 // Can only do this if the incoming index is somewhere in the interior of the string. 1299 // If index is at the end, there is no character there to look at. 1300 if (ix != ut->b) { 1301 U8_SET_CP_START(s8, 0, ix); 1302 } 1303 1304 // Swap the UText buffers. 1305 // We want to fill what was previously the alternate buffer, 1306 // and make what was the current buffer be the new alternate. 1307 UTF8Buf *u8b = (UTF8Buf *)ut->q; 1308 ut->q = ut->p; 1309 ut->p = u8b; 1310 1311 UChar *buf = u8b->buf; 1312 uint8_t *mapToNative = u8b->mapToNative; 1313 uint8_t *mapToUChars = u8b->mapToUChars; 1314 int32_t toUCharsMapStart = ix - (UTF8_TEXT_CHUNK_SIZE*3 + 1); 1315 int32_t destIx = UTF8_TEXT_CHUNK_SIZE+2; // Start in the overflow region 1316 // at end of buffer to leave room 1317 // for a surrogate pair at the 1318 // buffer start. 1319 int32_t srcIx = ix; 1320 int32_t bufNILimit = destIx; 1321 UChar32 c; 1322 1323 // Map to/from Native Indexes, fill in for the position at the end of 1324 // the buffer. 1325 // 1326 mapToNative[destIx] = (uint8_t)(srcIx - toUCharsMapStart); 1327 mapToUChars[srcIx - toUCharsMapStart] = (uint8_t)destIx; 1328 1329 // Fill the chunk buffer 1330 // Work backwards, filling from the end of the buffer towards the front. 1331 // 1332 while (destIx>2 && (srcIx - toUCharsMapStart > 5) && (srcIx > 0)) { 1333 srcIx--; 1334 destIx--; 1335 1336 // Get last byte of the UTF-8 character 1337 c = s8[srcIx]; 1338 if (c<0x80) { 1339 // Special case ASCII range for speed. 1340 buf[destIx] = (UChar)c; 1341 mapToUChars[srcIx - toUCharsMapStart] = (uint8_t)destIx; 1342 mapToNative[destIx] = (uint8_t)(srcIx - toUCharsMapStart); 1343 } else { 1344 // General case, handle everything non-ASCII. 1345 1346 int32_t sIx = srcIx; // ix of last byte of multi-byte u8 char 1347 1348 // Get the full character from the UTF8 string. 1349 // use code derived from tbe macros in utf8.h 1350 // Leaves srcIx pointing at the first byte of the UTF-8 char. 1351 // 1352 c=utf8_prevCharSafeBody(s8, 0, &srcIx, c, -3); 1353 // leaves srcIx at first byte of the multi-byte char. 1354 1355 // Store the character in UTF-16 buffer. 1356 if (c<0x10000) { 1357 buf[destIx] = (UChar)c; 1358 mapToNative[destIx] = (uint8_t)(srcIx - toUCharsMapStart); 1359 } else { 1360 buf[destIx] = U16_TRAIL(c); 1361 mapToNative[destIx] = (uint8_t)(srcIx - toUCharsMapStart); 1362 buf[--destIx] = U16_LEAD(c); 1363 mapToNative[destIx] = (uint8_t)(srcIx - toUCharsMapStart); 1364 } 1365 1366 // Fill in the map from native indexes to UChars buf index. 1367 do { 1368 mapToUChars[sIx-- - toUCharsMapStart] = (uint8_t)destIx; 1369 } while (sIx >= srcIx); 1370 1371 // Set native indexing limit to be the current position. 1372 // We are processing a non-ascii, non-native-indexing char now; 1373 // the limit will be here if the rest of the chars to be 1374 // added to this buffer are ascii. 1375 bufNILimit = destIx; 1376 } 1377 } 1378 u8b->bufNativeStart = srcIx; 1379 u8b->bufNativeLimit = ix; 1380 u8b->bufStartIdx = destIx; 1381 u8b->bufLimitIdx = UTF8_TEXT_CHUNK_SIZE+2; 1382 u8b->bufNILimit = bufNILimit - u8b->bufStartIdx; 1383 u8b->toUCharsMapStart = toUCharsMapStart; 1384 1385 ut->chunkContents = &buf[u8b->bufStartIdx]; 1386 ut->chunkLength = u8b->bufLimitIdx - u8b->bufStartIdx; 1387 ut->chunkOffset = ut->chunkLength; 1388 ut->chunkNativeStart = u8b->bufNativeStart; 1389 ut->chunkNativeLimit = u8b->bufNativeLimit; 1390 ut->nativeIndexingLimit = u8b->bufNILimit; 1391 return TRUE; 1392 } 1393 1394 } 1395 1396 1397 1398 // 1399 // This is a slightly modified copy of u_strFromUTF8, 1400 // Inserts a Replacement Char rather than failing on invalid UTF-8 1401 // Removes unnecessary features. 1402 // 1403 static UChar* 1404 utext_strFromUTF8(UChar *dest, 1405 int32_t destCapacity, 1406 int32_t *pDestLength, 1407 const char* src, 1408 int32_t srcLength, // required. NUL terminated not supported. 1409 UErrorCode *pErrorCode 1410 ) 1411 { 1412 1413 UChar *pDest = dest; 1414 UChar *pDestLimit = (dest!=NULL)?(dest+destCapacity):NULL; 1415 UChar32 ch=0; 1416 int32_t index = 0; 1417 int32_t reqLength = 0; 1418 uint8_t* pSrc = (uint8_t*) src; 1419 1420 1421 while((index < srcLength)&&(pDest<pDestLimit)){ 1422 ch = pSrc[index++]; 1423 if(ch <=0x7f){ 1424 *pDest++=(UChar)ch; 1425 }else{ 1426 ch=utf8_nextCharSafeBody(pSrc, &index, srcLength, ch, -3); 1427 if(U_IS_BMP(ch)){ 1428 *(pDest++)=(UChar)ch; 1429 }else{ 1430 *(pDest++)=U16_LEAD(ch); 1431 if(pDest<pDestLimit){ 1432 *(pDest++)=U16_TRAIL(ch); 1433 }else{ 1434 reqLength++; 1435 break; 1436 } 1437 } 1438 } 1439 } 1440 /* donot fill the dest buffer just count the UChars needed */ 1441 while(index < srcLength){ 1442 ch = pSrc[index++]; 1443 if(ch <= 0x7f){ 1444 reqLength++; 1445 }else{ 1446 ch=utf8_nextCharSafeBody(pSrc, &index, srcLength, ch, -3); 1447 reqLength+=U16_LENGTH(ch); 1448 } 1449 } 1450 1451 reqLength+=(int32_t)(pDest - dest); 1452 1453 if(pDestLength){ 1454 *pDestLength = reqLength; 1455 } 1456 1457 /* Terminate the buffer */ 1458 u_terminateUChars(dest,destCapacity,reqLength,pErrorCode); 1459 1460 return dest; 1461 } 1462 1463 1464 1465 static int32_t U_CALLCONV 1466 utf8TextExtract(UText *ut, 1467 int64_t start, int64_t limit, 1468 UChar *dest, int32_t destCapacity, 1469 UErrorCode *pErrorCode) { 1470 if(U_FAILURE(*pErrorCode)) { 1471 return 0; 1472 } 1473 if(destCapacity<0 || (dest==NULL && destCapacity>0)) { 1474 *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; 1475 return 0; 1476 } 1477 int32_t length = ut->b; 1478 int32_t start32 = pinIndex(start, length); 1479 int32_t limit32 = pinIndex(limit, length); 1480 1481 if(start32>limit32) { 1482 *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR; 1483 return 0; 1484 } 1485 1486 1487 // adjust the incoming indexes to land on code point boundaries if needed. 1488 // adjust by no more than three, because that is the largest number of trail bytes 1489 // in a well formed UTF8 character. 1490 const uint8_t *buf = (const uint8_t *)ut->context; 1491 int i; 1492 if (start32 < ut->chunkNativeLimit) { 1493 for (i=0; i<3; i++) { 1494 if (U8_IS_SINGLE(buf[start32]) || U8_IS_LEAD(buf[start32]) || start32==0) { 1495 break; 1496 } 1497 start32--; 1498 } 1499 } 1500 1501 if (limit32 < ut->chunkNativeLimit) { 1502 for (i=0; i<3; i++) { 1503 if (U8_IS_SINGLE(buf[limit32]) || U8_IS_LEAD(buf[limit32]) || limit32==0) { 1504 break; 1505 } 1506 limit32--; 1507 } 1508 } 1509 1510 // Do the actual extract. 1511 int32_t destLength=0; 1512 utext_strFromUTF8(dest, destCapacity, &destLength, 1513 (const char *)ut->context+start32, limit32-start32, 1514 pErrorCode); 1515 utf8TextAccess(ut, limit32, TRUE); 1516 return destLength; 1517 } 1518 1519 // 1520 // utf8TextMapOffsetToNative 1521 // 1522 // Map a chunk (UTF-16) offset to a native index. 1523 static int64_t U_CALLCONV 1524 utf8TextMapOffsetToNative(const UText *ut) { 1525 // 1526 UTF8Buf *u8b = (UTF8Buf *)ut->p; 1527 U_ASSERT(ut->chunkOffset>ut->nativeIndexingLimit && ut->chunkOffset<=ut->chunkLength); 1528 int32_t nativeOffset = u8b->mapToNative[ut->chunkOffset + u8b->bufStartIdx] + u8b->toUCharsMapStart; 1529 U_ASSERT(nativeOffset >= ut->chunkNativeStart && nativeOffset <= ut->chunkNativeLimit); 1530 return nativeOffset; 1531 } 1532 1533 // 1534 // Map a native index to the corrsponding chunk offset 1535 // 1536 static int32_t U_CALLCONV 1537 utf8TextMapIndexToUTF16(const UText *ut, int64_t index64) { 1538 U_ASSERT(index64 <= 0x7fffffff); 1539 int32_t index = (int32_t)index64; 1540 UTF8Buf *u8b = (UTF8Buf *)ut->p; 1541 U_ASSERT(index>=ut->chunkNativeStart+ut->nativeIndexingLimit); 1542 U_ASSERT(index<=ut->chunkNativeLimit); 1543 int32_t mapIndex = index - u8b->toUCharsMapStart; 1544 int32_t offset = u8b->mapToUChars[mapIndex] - u8b->bufStartIdx; 1545 U_ASSERT(offset>=0 && offset<=ut->chunkLength); 1546 return offset; 1547 } 1548 1549 static UText * U_CALLCONV 1550 utf8TextClone(UText *dest, const UText *src, UBool deep, UErrorCode *status) 1551 { 1552 // First do a generic shallow clone. Does everything needed for the UText struct itself. 1553 dest = shallowTextClone(dest, src, status); 1554 1555 // For deep clones, make a copy of the string. 1556 // The copied storage is owned by the newly created clone. 1557 // 1558 // TODO: There is an isssue with using utext_nativeLength(). 1559 // That function is non-const in cases where the input was NUL terminated 1560 // and the length has not yet been determined. 1561 // This function (clone()) is const. 1562 // There potentially a thread safety issue lurking here. 1563 // 1564 if (deep && U_SUCCESS(*status)) { 1565 int32_t len = (int32_t)utext_nativeLength((UText *)src); 1566 char *copyStr = (char *)uprv_malloc(len+1); 1567 if (copyStr == NULL) { 1568 *status = U_MEMORY_ALLOCATION_ERROR; 1569 } else { 1570 uprv_memcpy(copyStr, src->context, len+1); 1571 dest->context = copyStr; 1572 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT); 1573 } 1574 } 1575 return dest; 1576 } 1577 1578 1579 static void U_CALLCONV 1580 utf8TextClose(UText *ut) { 1581 // Most of the work of close is done by the generic UText framework close. 1582 // All that needs to be done here is to delete the UTF8 string if the UText 1583 // owns it. This occurs if the UText was created by cloning. 1584 if (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT)) { 1585 char *s = (char *)ut->context; 1586 uprv_free(s); 1587 ut->context = NULL; 1588 } 1589 } 1590 1591 U_CDECL_END 1592 1593 1594 static const struct UTextFuncs utf8Funcs = 1595 { 1596 sizeof(UTextFuncs), 1597 0, 0, 0, // Reserved alignment padding 1598 utf8TextClone, 1599 utf8TextLength, 1600 utf8TextAccess, 1601 utf8TextExtract, 1602 NULL, /* replace*/ 1603 NULL, /* copy */ 1604 utf8TextMapOffsetToNative, 1605 utf8TextMapIndexToUTF16, 1606 utf8TextClose, 1607 NULL, // spare 1 1608 NULL, // spare 2 1609 NULL // spare 3 1610 }; 1611 1612 1613 static const char gEmptyString[] = {0}; 1614 1615 U_CAPI UText * U_EXPORT2 1616 utext_openUTF8(UText *ut, const char *s, int64_t length, UErrorCode *status) { 1617 if(U_FAILURE(*status)) { 1618 return NULL; 1619 } 1620 if(s==NULL && length==0) { 1621 s = gEmptyString; 1622 } 1623 1624 if(s==NULL || length<-1 || length>INT32_MAX) { 1625 *status=U_ILLEGAL_ARGUMENT_ERROR; 1626 return NULL; 1627 } 1628 1629 ut = utext_setup(ut, sizeof(UTF8Buf) * 2, status); 1630 if (U_FAILURE(*status)) { 1631 return ut; 1632 } 1633 1634 ut->pFuncs = &utf8Funcs; 1635 ut->context = s; 1636 ut->b = (int32_t)length; 1637 ut->c = (int32_t)length; 1638 if (ut->c < 0) { 1639 ut->c = 0; 1640 ut->providerProperties |= I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 1641 } 1642 ut->p = ut->pExtra; 1643 ut->q = (char *)ut->pExtra + sizeof(UTF8Buf); 1644 return ut; 1645 1646 } 1647 1648 1649 1650 1651 1652 1653 1654 1655 //------------------------------------------------------------------------------ 1656 // 1657 // UText implementation wrapper for Replaceable (read/write) 1658 // 1659 // Use of UText data members: 1660 // context pointer to Replaceable. 1661 // p pointer to Replaceable if it is owned by the UText. 1662 // 1663 //------------------------------------------------------------------------------ 1664 1665 1666 1667 // minimum chunk size for this implementation: 3 1668 // to allow for possible trimming for code point boundaries 1669 enum { REP_TEXT_CHUNK_SIZE=10 }; 1670 1671 struct ReplExtra { 1672 /* 1673 * Chunk UChars. 1674 * +1 to simplify filling with surrogate pair at the end. 1675 */ 1676 UChar s[REP_TEXT_CHUNK_SIZE+1]; 1677 }; 1678 1679 1680 U_CDECL_BEGIN 1681 1682 static UText * U_CALLCONV 1683 repTextClone(UText *dest, const UText *src, UBool deep, UErrorCode *status) { 1684 // First do a generic shallow clone. Does everything needed for the UText struct itself. 1685 dest = shallowTextClone(dest, src, status); 1686 1687 // For deep clones, make a copy of the Replaceable. 1688 // The copied Replaceable storage is owned by the newly created UText clone. 1689 // A non-NULL pointer in UText.p is the signal to the close() function to delete 1690 // it. 1691 // 1692 if (deep && U_SUCCESS(*status)) { 1693 const Replaceable *replSrc = (const Replaceable *)src->context; 1694 dest->context = replSrc->clone(); 1695 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT); 1696 1697 // with deep clone, the copy is writable, even when the source is not. 1698 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_WRITABLE); 1699 } 1700 return dest; 1701 } 1702 1703 1704 static void U_CALLCONV 1705 repTextClose(UText *ut) { 1706 // Most of the work of close is done by the generic UText framework close. 1707 // All that needs to be done here is delete the Replaceable if the UText 1708 // owns it. This occurs if the UText was created by cloning. 1709 if (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT)) { 1710 Replaceable *rep = (Replaceable *)ut->context; 1711 delete rep; 1712 ut->context = NULL; 1713 } 1714 } 1715 1716 1717 static int64_t U_CALLCONV 1718 repTextLength(UText *ut) { 1719 const Replaceable *replSrc = (const Replaceable *)ut->context; 1720 int32_t len = replSrc->length(); 1721 return len; 1722 } 1723 1724 1725 static UBool U_CALLCONV 1726 repTextAccess(UText *ut, int64_t index, UBool forward) { 1727 const Replaceable *rep=(const Replaceable *)ut->context; 1728 int32_t length=rep->length(); // Full length of the input text (bigger than a chunk) 1729 1730 // clip the requested index to the limits of the text. 1731 int32_t index32 = pinIndex(index, length); 1732 U_ASSERT(index<=INT32_MAX); 1733 1734 1735 /* 1736 * Compute start/limit boundaries around index, for a segment of text 1737 * to be extracted. 1738 * To allow for the possibility that our user gave an index to the trailing 1739 * half of a surrogate pair, we must request one extra preceding UChar when 1740 * going in the forward direction. This will ensure that the buffer has the 1741 * entire code point at the specified index. 1742 */ 1743 if(forward) { 1744 1745 if (index32>=ut->chunkNativeStart && index32<ut->chunkNativeLimit) { 1746 // Buffer already contains the requested position. 1747 ut->chunkOffset = (int32_t)(index - ut->chunkNativeStart); 1748 return TRUE; 1749 } 1750 if (index32>=length && ut->chunkNativeLimit==length) { 1751 // Request for end of string, and buffer already extends up to it. 1752 // Can't get the data, but don't change the buffer. 1753 ut->chunkOffset = length - (int32_t)ut->chunkNativeStart; 1754 return FALSE; 1755 } 1756 1757 ut->chunkNativeLimit = index + REP_TEXT_CHUNK_SIZE - 1; 1758 // Going forward, so we want to have the buffer with stuff at and beyond 1759 // the requested index. The -1 gets us one code point before the 1760 // requested index also, to handle the case of the index being on 1761 // a trail surrogate of a surrogate pair. 1762 if(ut->chunkNativeLimit > length) { 1763 ut->chunkNativeLimit = length; 1764 } 1765 // unless buffer ran off end, start is index-1. 1766 ut->chunkNativeStart = ut->chunkNativeLimit - REP_TEXT_CHUNK_SIZE; 1767 if(ut->chunkNativeStart < 0) { 1768 ut->chunkNativeStart = 0; 1769 } 1770 } else { 1771 // Reverse iteration. Fill buffer with data preceding the requested index. 1772 if (index32>ut->chunkNativeStart && index32<=ut->chunkNativeLimit) { 1773 // Requested position already in buffer. 1774 ut->chunkOffset = index32 - (int32_t)ut->chunkNativeStart; 1775 return TRUE; 1776 } 1777 if (index32==0 && ut->chunkNativeStart==0) { 1778 // Request for start, buffer already begins at start. 1779 // No data, but keep the buffer as is. 1780 ut->chunkOffset = 0; 1781 return FALSE; 1782 } 1783 1784 // Figure out the bounds of the chunk to extract for reverse iteration. 1785 // Need to worry about chunk not splitting surrogate pairs, and while still 1786 // containing the data we need. 1787 // Fix by requesting a chunk that includes an extra UChar at the end. 1788 // If this turns out to be a lead surrogate, we can lop it off and still have 1789 // the data we wanted. 1790 ut->chunkNativeStart = index32 + 1 - REP_TEXT_CHUNK_SIZE; 1791 if (ut->chunkNativeStart < 0) { 1792 ut->chunkNativeStart = 0; 1793 } 1794 1795 ut->chunkNativeLimit = index32 + 1; 1796 if (ut->chunkNativeLimit > length) { 1797 ut->chunkNativeLimit = length; 1798 } 1799 } 1800 1801 // Extract the new chunk of text from the Replaceable source. 1802 ReplExtra *ex = (ReplExtra *)ut->pExtra; 1803 // UnicodeString with its buffer a writable alias to the chunk buffer 1804 UnicodeString buffer(ex->s, 0 /*buffer length*/, REP_TEXT_CHUNK_SIZE /*buffer capacity*/); 1805 rep->extractBetween((int32_t)ut->chunkNativeStart, (int32_t)ut->chunkNativeLimit, buffer); 1806 1807 ut->chunkContents = ex->s; 1808 ut->chunkLength = (int32_t)(ut->chunkNativeLimit - ut->chunkNativeStart); 1809 ut->chunkOffset = (int32_t)(index32 - ut->chunkNativeStart); 1810 1811 // Surrogate pairs from the input text must not span chunk boundaries. 1812 // If end of chunk could be the start of a surrogate, trim it off. 1813 if (ut->chunkNativeLimit < length && 1814 U16_IS_LEAD(ex->s[ut->chunkLength-1])) { 1815 ut->chunkLength--; 1816 ut->chunkNativeLimit--; 1817 if (ut->chunkOffset > ut->chunkLength) { 1818 ut->chunkOffset = ut->chunkLength; 1819 } 1820 } 1821 1822 // if the first UChar in the chunk could be the trailing half of a surrogate pair, 1823 // trim it off. 1824 if(ut->chunkNativeStart>0 && U16_IS_TRAIL(ex->s[0])) { 1825 ++(ut->chunkContents); 1826 ++(ut->chunkNativeStart); 1827 --(ut->chunkLength); 1828 --(ut->chunkOffset); 1829 } 1830 1831 // adjust the index/chunkOffset to a code point boundary 1832 U16_SET_CP_START(ut->chunkContents, 0, ut->chunkOffset); 1833 1834 // Use fast indexing for get/setNativeIndex() 1835 ut->nativeIndexingLimit = ut->chunkLength; 1836 1837 return TRUE; 1838 } 1839 1840 1841 1842 static int32_t U_CALLCONV 1843 repTextExtract(UText *ut, 1844 int64_t start, int64_t limit, 1845 UChar *dest, int32_t destCapacity, 1846 UErrorCode *status) { 1847 const Replaceable *rep=(const Replaceable *)ut->context; 1848 int32_t length=rep->length(); 1849 1850 if(U_FAILURE(*status)) { 1851 return 0; 1852 } 1853 if(destCapacity<0 || (dest==NULL && destCapacity>0)) { 1854 *status=U_ILLEGAL_ARGUMENT_ERROR; 1855 } 1856 if(start>limit) { 1857 *status=U_INDEX_OUTOFBOUNDS_ERROR; 1858 return 0; 1859 } 1860 1861 int32_t start32 = pinIndex(start, length); 1862 int32_t limit32 = pinIndex(limit, length); 1863 1864 // adjust start, limit if they point to trail half of surrogates 1865 if (start32<length && U16_IS_TRAIL(rep->charAt(start32)) && 1866 U_IS_SUPPLEMENTARY(rep->char32At(start32))){ 1867 start32--; 1868 } 1869 if (limit32<length && U16_IS_TRAIL(rep->charAt(limit32)) && 1870 U_IS_SUPPLEMENTARY(rep->char32At(limit32))){ 1871 limit32--; 1872 } 1873 1874 length=limit32-start32; 1875 if(length>destCapacity) { 1876 limit32 = start32 + destCapacity; 1877 } 1878 UnicodeString buffer(dest, 0, destCapacity); // writable alias 1879 rep->extractBetween(start32, limit32, buffer); 1880 repTextAccess(ut, limit32, TRUE); 1881 1882 return u_terminateUChars(dest, destCapacity, length, status); 1883 } 1884 1885 static int32_t U_CALLCONV 1886 repTextReplace(UText *ut, 1887 int64_t start, int64_t limit, 1888 const UChar *src, int32_t length, 1889 UErrorCode *status) { 1890 Replaceable *rep=(Replaceable *)ut->context; 1891 int32_t oldLength; 1892 1893 if(U_FAILURE(*status)) { 1894 return 0; 1895 } 1896 if(src==NULL && length!=0) { 1897 *status=U_ILLEGAL_ARGUMENT_ERROR; 1898 return 0; 1899 } 1900 oldLength=rep->length(); // will subtract from new length 1901 if(start>limit ) { 1902 *status=U_INDEX_OUTOFBOUNDS_ERROR; 1903 return 0; 1904 } 1905 1906 int32_t start32 = pinIndex(start, oldLength); 1907 int32_t limit32 = pinIndex(limit, oldLength); 1908 1909 // Snap start & limit to code point boundaries. 1910 if (start32<oldLength && U16_IS_TRAIL(rep->charAt(start32)) && 1911 start32>0 && U16_IS_LEAD(rep->charAt(start32-1))) 1912 { 1913 start32--; 1914 } 1915 if (limit32<oldLength && U16_IS_LEAD(rep->charAt(limit32-1)) && 1916 U16_IS_TRAIL(rep->charAt(limit32))) 1917 { 1918 limit32++; 1919 } 1920 1921 // Do the actual replace operation using methods of the Replaceable class 1922 UnicodeString replStr((UBool)(length<0), src, length); // read-only alias 1923 rep->handleReplaceBetween(start32, limit32, replStr); 1924 int32_t newLength = rep->length(); 1925 int32_t lengthDelta = newLength - oldLength; 1926 1927 // Is the UText chunk buffer OK? 1928 if (ut->chunkNativeLimit > start32) { 1929 // this replace operation may have impacted the current chunk. 1930 // invalidate it, which will force a reload on the next access. 1931 invalidateChunk(ut); 1932 } 1933 1934 // set the iteration position to the end of the newly inserted replacement text. 1935 int32_t newIndexPos = limit32 + lengthDelta; 1936 repTextAccess(ut, newIndexPos, TRUE); 1937 1938 return lengthDelta; 1939 } 1940 1941 1942 static void U_CALLCONV 1943 repTextCopy(UText *ut, 1944 int64_t start, int64_t limit, 1945 int64_t destIndex, 1946 UBool move, 1947 UErrorCode *status) 1948 { 1949 Replaceable *rep=(Replaceable *)ut->context; 1950 int32_t length=rep->length(); 1951 1952 if(U_FAILURE(*status)) { 1953 return; 1954 } 1955 if (start>limit || (start<destIndex && destIndex<limit)) 1956 { 1957 *status=U_INDEX_OUTOFBOUNDS_ERROR; 1958 return; 1959 } 1960 1961 int32_t start32 = pinIndex(start, length); 1962 int32_t limit32 = pinIndex(limit, length); 1963 int32_t destIndex32 = pinIndex(destIndex, length); 1964 1965 // TODO: snap input parameters to code point boundaries. 1966 1967 if(move) { 1968 // move: copy to destIndex, then replace original with nothing 1969 int32_t segLength=limit32-start32; 1970 rep->copy(start32, limit32, destIndex32); 1971 if(destIndex32<start32) { 1972 start32+=segLength; 1973 limit32+=segLength; 1974 } 1975 rep->handleReplaceBetween(start32, limit32, UnicodeString()); 1976 } else { 1977 // copy 1978 rep->copy(start32, limit32, destIndex32); 1979 } 1980 1981 // If the change to the text touched the region in the chunk buffer, 1982 // invalidate the buffer. 1983 int32_t firstAffectedIndex = destIndex32; 1984 if (move && start32<firstAffectedIndex) { 1985 firstAffectedIndex = start32; 1986 } 1987 if (firstAffectedIndex < ut->chunkNativeLimit) { 1988 // changes may have affected range covered by the chunk 1989 invalidateChunk(ut); 1990 } 1991 1992 // Put iteration position at the newly inserted (moved) block, 1993 int32_t nativeIterIndex = destIndex32 + limit32 - start32; 1994 if (move && destIndex32>start32) { 1995 // moved a block of text towards the end of the string. 1996 nativeIterIndex = destIndex32; 1997 } 1998 1999 // Set position, reload chunk if needed. 2000 repTextAccess(ut, nativeIterIndex, TRUE); 2001 } 2002 2003 static const struct UTextFuncs repFuncs = 2004 { 2005 sizeof(UTextFuncs), 2006 0, 0, 0, // Reserved alignment padding 2007 repTextClone, 2008 repTextLength, 2009 repTextAccess, 2010 repTextExtract, 2011 repTextReplace, 2012 repTextCopy, 2013 NULL, // MapOffsetToNative, 2014 NULL, // MapIndexToUTF16, 2015 repTextClose, 2016 NULL, // spare 1 2017 NULL, // spare 2 2018 NULL // spare 3 2019 }; 2020 2021 2022 U_CAPI UText * U_EXPORT2 2023 utext_openReplaceable(UText *ut, Replaceable *rep, UErrorCode *status) 2024 { 2025 if(U_FAILURE(*status)) { 2026 return NULL; 2027 } 2028 if(rep==NULL) { 2029 *status=U_ILLEGAL_ARGUMENT_ERROR; 2030 return NULL; 2031 } 2032 ut = utext_setup(ut, sizeof(ReplExtra), status); 2033 if(U_FAILURE(*status)) { 2034 return ut; 2035 } 2036 2037 ut->providerProperties = I32_FLAG(UTEXT_PROVIDER_WRITABLE); 2038 if(rep->hasMetaData()) { 2039 ut->providerProperties |=I32_FLAG(UTEXT_PROVIDER_HAS_META_DATA); 2040 } 2041 2042 ut->pFuncs = &repFuncs; 2043 ut->context = rep; 2044 return ut; 2045 } 2046 2047 U_CDECL_END 2048 2049 2050 2051 2052 2053 2054 2055 2056 //------------------------------------------------------------------------------ 2057 // 2058 // UText implementation for UnicodeString (read/write) and 2059 // for const UnicodeString (read only) 2060 // (same implementation, only the flags are different) 2061 // 2062 // Use of UText data members: 2063 // context pointer to UnicodeString 2064 // p pointer to UnicodeString IF this UText owns the string 2065 // and it must be deleted on close(). NULL otherwise. 2066 // 2067 //------------------------------------------------------------------------------ 2068 2069 U_CDECL_BEGIN 2070 2071 2072 static UText * U_CALLCONV 2073 unistrTextClone(UText *dest, const UText *src, UBool deep, UErrorCode *status) { 2074 // First do a generic shallow clone. Does everything needed for the UText struct itself. 2075 dest = shallowTextClone(dest, src, status); 2076 2077 // For deep clones, make a copy of the UnicodeSring. 2078 // The copied UnicodeString storage is owned by the newly created UText clone. 2079 // A non-NULL pointer in UText.p is the signal to the close() function to delete 2080 // the UText. 2081 // 2082 if (deep && U_SUCCESS(*status)) { 2083 const UnicodeString *srcString = (const UnicodeString *)src->context; 2084 dest->context = new UnicodeString(*srcString); 2085 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT); 2086 2087 // with deep clone, the copy is writable, even when the source is not. 2088 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_WRITABLE); 2089 } 2090 return dest; 2091 } 2092 2093 static void U_CALLCONV 2094 unistrTextClose(UText *ut) { 2095 // Most of the work of close is done by the generic UText framework close. 2096 // All that needs to be done here is delete the UnicodeString if the UText 2097 // owns it. This occurs if the UText was created by cloning. 2098 if (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT)) { 2099 UnicodeString *str = (UnicodeString *)ut->context; 2100 delete str; 2101 ut->context = NULL; 2102 } 2103 } 2104 2105 2106 static int64_t U_CALLCONV 2107 unistrTextLength(UText *t) { 2108 return ((const UnicodeString *)t->context)->length(); 2109 } 2110 2111 2112 static UBool U_CALLCONV 2113 unistrTextAccess(UText *ut, int64_t index, UBool forward) { 2114 int32_t length = ut->chunkLength; 2115 ut->chunkOffset = pinIndex(index, length); 2116 2117 // Check whether request is at the start or end 2118 UBool retVal = (forward && index<length) || (!forward && index>0); 2119 return retVal; 2120 } 2121 2122 2123 2124 static int32_t U_CALLCONV 2125 unistrTextExtract(UText *t, 2126 int64_t start, int64_t limit, 2127 UChar *dest, int32_t destCapacity, 2128 UErrorCode *pErrorCode) { 2129 const UnicodeString *us=(const UnicodeString *)t->context; 2130 int32_t length=us->length(); 2131 2132 if(U_FAILURE(*pErrorCode)) { 2133 return 0; 2134 } 2135 if(destCapacity<0 || (dest==NULL && destCapacity>0)) { 2136 *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; 2137 } 2138 if(start<0 || start>limit) { 2139 *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR; 2140 return 0; 2141 } 2142 2143 int32_t start32 = start<length ? us->getChar32Start((int32_t)start) : length; 2144 int32_t limit32 = limit<length ? us->getChar32Start((int32_t)limit) : length; 2145 2146 length=limit32-start32; 2147 if (destCapacity>0 && dest!=NULL) { 2148 int32_t trimmedLength = length; 2149 if(trimmedLength>destCapacity) { 2150 trimmedLength=destCapacity; 2151 } 2152 us->extract(start32, trimmedLength, dest); 2153 t->chunkOffset = start32+trimmedLength; 2154 } else { 2155 t->chunkOffset = start32; 2156 } 2157 u_terminateUChars(dest, destCapacity, length, pErrorCode); 2158 return length; 2159 } 2160 2161 static int32_t U_CALLCONV 2162 unistrTextReplace(UText *ut, 2163 int64_t start, int64_t limit, 2164 const UChar *src, int32_t length, 2165 UErrorCode *pErrorCode) { 2166 UnicodeString *us=(UnicodeString *)ut->context; 2167 int32_t oldLength; 2168 2169 if(U_FAILURE(*pErrorCode)) { 2170 return 0; 2171 } 2172 if(src==NULL && length!=0) { 2173 *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; 2174 } 2175 if(start>limit) { 2176 *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR; 2177 return 0; 2178 } 2179 oldLength=us->length(); 2180 int32_t start32 = pinIndex(start, oldLength); 2181 int32_t limit32 = pinIndex(limit, oldLength); 2182 if (start32 < oldLength) { 2183 start32 = us->getChar32Start(start32); 2184 } 2185 if (limit32 < oldLength) { 2186 limit32 = us->getChar32Start(limit32); 2187 } 2188 2189 // replace 2190 us->replace(start32, limit32-start32, src, length); 2191 int32_t newLength = us->length(); 2192 2193 // Update the chunk description. 2194 ut->chunkContents = us->getBuffer(); 2195 ut->chunkLength = newLength; 2196 ut->chunkNativeLimit = newLength; 2197 ut->nativeIndexingLimit = newLength; 2198 2199 // Set iteration position to the point just following the newly inserted text. 2200 int32_t lengthDelta = newLength - oldLength; 2201 ut->chunkOffset = limit32 + lengthDelta; 2202 2203 return lengthDelta; 2204 } 2205 2206 static void U_CALLCONV 2207 unistrTextCopy(UText *ut, 2208 int64_t start, int64_t limit, 2209 int64_t destIndex, 2210 UBool move, 2211 UErrorCode *pErrorCode) { 2212 UnicodeString *us=(UnicodeString *)ut->context; 2213 int32_t length=us->length(); 2214 2215 if(U_FAILURE(*pErrorCode)) { 2216 return; 2217 } 2218 int32_t start32 = pinIndex(start, length); 2219 int32_t limit32 = pinIndex(limit, length); 2220 int32_t destIndex32 = pinIndex(destIndex, length); 2221 2222 if( start32>limit32 || (start32<destIndex32 && destIndex32<limit32)) { 2223 *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR; 2224 return; 2225 } 2226 2227 if(move) { 2228 // move: copy to destIndex, then replace original with nothing 2229 int32_t segLength=limit32-start32; 2230 us->copy(start32, limit32, destIndex32); 2231 if(destIndex32<start32) { 2232 start32+=segLength; 2233 } 2234 us->replace(start32, segLength, NULL, 0); 2235 } else { 2236 // copy 2237 us->copy(start32, limit32, destIndex32); 2238 } 2239 2240 // update chunk description, set iteration position. 2241 ut->chunkContents = us->getBuffer(); 2242 if (move==FALSE) { 2243 // copy operation, string length grows 2244 ut->chunkLength += limit32-start32; 2245 ut->chunkNativeLimit = ut->chunkLength; 2246 ut->nativeIndexingLimit = ut->chunkLength; 2247 } 2248 2249 // Iteration position to end of the newly inserted text. 2250 ut->chunkOffset = destIndex32+limit32-start32; 2251 if (move && destIndex32>start32) { 2252 ut->chunkOffset = destIndex32; 2253 } 2254 2255 } 2256 2257 static const struct UTextFuncs unistrFuncs = 2258 { 2259 sizeof(UTextFuncs), 2260 0, 0, 0, // Reserved alignment padding 2261 unistrTextClone, 2262 unistrTextLength, 2263 unistrTextAccess, 2264 unistrTextExtract, 2265 unistrTextReplace, 2266 unistrTextCopy, 2267 NULL, // MapOffsetToNative, 2268 NULL, // MapIndexToUTF16, 2269 unistrTextClose, 2270 NULL, // spare 1 2271 NULL, // spare 2 2272 NULL // spare 3 2273 }; 2274 2275 2276 2277 U_CDECL_END 2278 2279 2280 U_CAPI UText * U_EXPORT2 2281 utext_openUnicodeString(UText *ut, UnicodeString *s, UErrorCode *status) { 2282 ut = utext_openConstUnicodeString(ut, s, status); 2283 if (U_SUCCESS(*status)) { 2284 ut->providerProperties |= I32_FLAG(UTEXT_PROVIDER_WRITABLE); 2285 } 2286 return ut; 2287 } 2288 2289 2290 2291 U_CAPI UText * U_EXPORT2 2292 utext_openConstUnicodeString(UText *ut, const UnicodeString *s, UErrorCode *status) { 2293 if (U_SUCCESS(*status) && s->isBogus()) { 2294 // The UnicodeString is bogus, but we still need to detach the UText 2295 // from whatever it was hooked to before, if anything. 2296 utext_openUChars(ut, NULL, 0, status); 2297 *status = U_ILLEGAL_ARGUMENT_ERROR; 2298 return ut; 2299 } 2300 ut = utext_setup(ut, 0, status); 2301 // note: use the standard (writable) function table for UnicodeString. 2302 // The flag settings disable writing, so having the functions in 2303 // the table is harmless. 2304 if (U_SUCCESS(*status)) { 2305 ut->pFuncs = &unistrFuncs; 2306 ut->context = s; 2307 ut->providerProperties = I32_FLAG(UTEXT_PROVIDER_STABLE_CHUNKS); 2308 ut->chunkContents = s->getBuffer(); 2309 ut->chunkLength = s->length(); 2310 ut->chunkNativeStart = 0; 2311 ut->chunkNativeLimit = ut->chunkLength; 2312 ut->nativeIndexingLimit = ut->chunkLength; 2313 } 2314 return ut; 2315 } 2316 2317 //------------------------------------------------------------------------------ 2318 // 2319 // UText implementation for const UChar * strings 2320 // 2321 // Use of UText data members: 2322 // context pointer to UnicodeString 2323 // a length. -1 if not yet known. 2324 // 2325 // TODO: support 64 bit lengths. 2326 // 2327 //------------------------------------------------------------------------------ 2328 2329 U_CDECL_BEGIN 2330 2331 2332 static UText * U_CALLCONV 2333 ucstrTextClone(UText *dest, const UText * src, UBool deep, UErrorCode * status) { 2334 // First do a generic shallow clone. 2335 dest = shallowTextClone(dest, src, status); 2336 2337 // For deep clones, make a copy of the string. 2338 // The copied storage is owned by the newly created clone. 2339 // A non-NULL pointer in UText.p is the signal to the close() function to delete 2340 // it. 2341 // 2342 if (deep && U_SUCCESS(*status)) { 2343 U_ASSERT(utext_nativeLength(dest) < INT32_MAX); 2344 int32_t len = (int32_t)utext_nativeLength(dest); 2345 2346 // The cloned string IS going to be NUL terminated, whether or not the original was. 2347 const UChar *srcStr = (const UChar *)src->context; 2348 UChar *copyStr = (UChar *)uprv_malloc((len+1) * sizeof(UChar)); 2349 if (copyStr == NULL) { 2350 *status = U_MEMORY_ALLOCATION_ERROR; 2351 } else { 2352 int64_t i; 2353 for (i=0; i<len; i++) { 2354 copyStr[i] = srcStr[i]; 2355 } 2356 copyStr[len] = 0; 2357 dest->context = copyStr; 2358 dest->providerProperties |= I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT); 2359 } 2360 } 2361 return dest; 2362 } 2363 2364 2365 static void U_CALLCONV 2366 ucstrTextClose(UText *ut) { 2367 // Most of the work of close is done by the generic UText framework close. 2368 // All that needs to be done here is delete the string if the UText 2369 // owns it. This occurs if the UText was created by cloning. 2370 if (ut->providerProperties & I32_FLAG(UTEXT_PROVIDER_OWNS_TEXT)) { 2371 UChar *s = (UChar *)ut->context; 2372 uprv_free(s); 2373 ut->context = NULL; 2374 } 2375 } 2376 2377 2378 2379 static int64_t U_CALLCONV 2380 ucstrTextLength(UText *ut) { 2381 if (ut->a < 0) { 2382 // null terminated, we don't yet know the length. Scan for it. 2383 // Access is not convenient for doing this 2384 // because the current interation postion can't be changed. 2385 const UChar *str = (const UChar *)ut->context; 2386 for (;;) { 2387 if (str[ut->chunkNativeLimit] == 0) { 2388 break; 2389 } 2390 ut->chunkNativeLimit++; 2391 } 2392 ut->a = ut->chunkNativeLimit; 2393 ut->chunkLength = (int32_t)ut->chunkNativeLimit; 2394 ut->nativeIndexingLimit = ut->chunkLength; 2395 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 2396 } 2397 return ut->a; 2398 } 2399 2400 2401 static UBool U_CALLCONV 2402 ucstrTextAccess(UText *ut, int64_t index, UBool forward) { 2403 const UChar *str = (const UChar *)ut->context; 2404 2405 // pin the requested index to the bounds of the string, 2406 // and set current iteration position. 2407 if (index<0) { 2408 index = 0; 2409 } else if (index < ut->chunkNativeLimit) { 2410 // The request data is within the chunk as it is known so far. 2411 // Put index on a code point boundary. 2412 U16_SET_CP_START(str, 0, index); 2413 } else if (ut->a >= 0) { 2414 // We know the length of this string, and the user is requesting something 2415 // at or beyond the length. Pin the requested index to the length. 2416 index = ut->a; 2417 } else { 2418 // Null terminated string, length not yet known, and the requested index 2419 // is beyond where we have scanned so far. 2420 // Scan to 32 UChars beyond the requested index. The strategy here is 2421 // to avoid fully scanning a long string when the caller only wants to 2422 // see a few characters at its beginning. 2423 int32_t scanLimit = (int32_t)index + 32; 2424 if ((index + 32)>INT32_MAX || (index + 32)<0 ) { // note: int64 expression 2425 scanLimit = INT32_MAX; 2426 } 2427 2428 int32_t chunkLimit = (int32_t)ut->chunkNativeLimit; 2429 for (; chunkLimit<scanLimit; chunkLimit++) { 2430 if (str[chunkLimit] == 0) { 2431 // We found the end of the string. Remember it, pin the requested index to it, 2432 // and bail out of here. 2433 ut->a = chunkLimit; 2434 ut->chunkLength = chunkLimit; 2435 ut->nativeIndexingLimit = chunkLimit; 2436 if (index >= chunkLimit) { 2437 index = chunkLimit; 2438 } else { 2439 U16_SET_CP_START(str, 0, index); 2440 } 2441 2442 ut->chunkNativeLimit = chunkLimit; 2443 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 2444 goto breakout; 2445 } 2446 } 2447 // We scanned through the next batch of UChars without finding the end. 2448 U16_SET_CP_START(str, 0, index); 2449 if (chunkLimit == INT32_MAX) { 2450 // Scanned to the limit of a 32 bit length. 2451 // Forceably trim the overlength string back so length fits in int32 2452 // TODO: add support for 64 bit strings. 2453 ut->a = chunkLimit; 2454 ut->chunkLength = chunkLimit; 2455 ut->nativeIndexingLimit = chunkLimit; 2456 if (index > chunkLimit) { 2457 index = chunkLimit; 2458 } 2459 ut->chunkNativeLimit = chunkLimit; 2460 ut->providerProperties &= ~I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 2461 } else { 2462 // The endpoint of a chunk must not be left in the middle of a surrogate pair. 2463 // If the current end is on a lead surrogate, back the end up by one. 2464 // It doesn't matter if the end char happens to be an unpaired surrogate, 2465 // and it's simpler not to worry about it. 2466 if (U16_IS_LEAD(str[chunkLimit-1])) { 2467 --chunkLimit; 2468 } 2469 // Null-terminated chunk with end still unknown. 2470 // Update the chunk length to reflect what has been scanned thus far. 2471 // That the full length is still unknown is (still) flagged by 2472 // ut->a being < 0. 2473 ut->chunkNativeLimit = chunkLimit; 2474 ut->nativeIndexingLimit = chunkLimit; 2475 ut->chunkLength = chunkLimit; 2476 } 2477 2478 } 2479 breakout: 2480 U_ASSERT(index<=INT32_MAX); 2481 ut->chunkOffset = (int32_t)index; 2482 2483 // Check whether request is at the start or end 2484 UBool retVal = (forward && index<ut->chunkNativeLimit) || (!forward && index>0); 2485 return retVal; 2486 } 2487 2488 2489 2490 static int32_t U_CALLCONV 2491 ucstrTextExtract(UText *ut, 2492 int64_t start, int64_t limit, 2493 UChar *dest, int32_t destCapacity, 2494 UErrorCode *pErrorCode) 2495 { 2496 if(U_FAILURE(*pErrorCode)) { 2497 return 0; 2498 } 2499 if(destCapacity<0 || (dest==NULL && destCapacity>0) || start>limit) { 2500 *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; 2501 return 0; 2502 } 2503 2504 //const UChar *s=(const UChar *)ut->context; 2505 int32_t si, di; 2506 2507 int32_t start32; 2508 int32_t limit32; 2509 2510 // Access the start. Does two things we need: 2511 // Pins 'start' to the length of the string, if it came in out-of-bounds. 2512 // Snaps 'start' to the beginning of a code point. 2513 ucstrTextAccess(ut, start, TRUE); 2514 const UChar *s=ut->chunkContents; 2515 start32 = ut->chunkOffset; 2516 2517 int32_t strLength=(int32_t)ut->a; 2518 if (strLength >= 0) { 2519 limit32 = pinIndex(limit, strLength); 2520 } else { 2521 limit32 = pinIndex(limit, INT32_MAX); 2522 } 2523 di = 0; 2524 for (si=start32; si<limit32; si++) { 2525 if (strLength<0 && s[si]==0) { 2526 // Just hit the end of a null-terminated string. 2527 ut->a = si; // set string length for this UText 2528 ut->chunkNativeLimit = si; 2529 ut->chunkLength = si; 2530 ut->nativeIndexingLimit = si; 2531 strLength = si; 2532 limit32 = si; 2533 break; 2534 } 2535 U_ASSERT(di>=0); /* to ensure di never exceeds INT32_MAX, which must not happen logically */ 2536 if (di<destCapacity) { 2537 // only store if there is space. 2538 dest[di] = s[si]; 2539 } else { 2540 if (strLength>=0) { 2541 // We have filled the destination buffer, and the string length is known. 2542 // Cut the loop short. There is no need to scan string termination. 2543 di = limit32 - start32; 2544 si = limit32; 2545 break; 2546 } 2547 } 2548 di++; 2549 } 2550 2551 // If the limit index points to a lead surrogate of a pair, 2552 // add the corresponding trail surrogate to the destination. 2553 if (si>0 && U16_IS_LEAD(s[si-1]) && 2554 ((si<strLength || strLength<0) && U16_IS_TRAIL(s[si]))) 2555 { 2556 if (di<destCapacity) { 2557 // store only if there is space in the output buffer. 2558 dest[di++] = s[si]; 2559 } 2560 si++; 2561 } 2562 2563 // Put iteration position at the point just following the extracted text 2564 if (si <= ut->chunkNativeLimit) { 2565 ut->chunkOffset = si; 2566 } else { 2567 ucstrTextAccess(ut, si, TRUE); 2568 } 2569 2570 // Add a terminating NUL if space in the buffer permits, 2571 // and set the error status as required. 2572 u_terminateUChars(dest, destCapacity, di, pErrorCode); 2573 return di; 2574 } 2575 2576 static const struct UTextFuncs ucstrFuncs = 2577 { 2578 sizeof(UTextFuncs), 2579 0, 0, 0, // Reserved alignment padding 2580 ucstrTextClone, 2581 ucstrTextLength, 2582 ucstrTextAccess, 2583 ucstrTextExtract, 2584 NULL, // Replace 2585 NULL, // Copy 2586 NULL, // MapOffsetToNative, 2587 NULL, // MapIndexToUTF16, 2588 ucstrTextClose, 2589 NULL, // spare 1 2590 NULL, // spare 2 2591 NULL, // spare 3 2592 }; 2593 2594 U_CDECL_END 2595 2596 static const UChar gEmptyUString[] = {0}; 2597 2598 U_CAPI UText * U_EXPORT2 2599 utext_openUChars(UText *ut, const UChar *s, int64_t length, UErrorCode *status) { 2600 if (U_FAILURE(*status)) { 2601 return NULL; 2602 } 2603 if(s==NULL && length==0) { 2604 s = gEmptyUString; 2605 } 2606 if (s==NULL || length < -1 || length>INT32_MAX) { 2607 *status = U_ILLEGAL_ARGUMENT_ERROR; 2608 return NULL; 2609 } 2610 ut = utext_setup(ut, 0, status); 2611 if (U_SUCCESS(*status)) { 2612 ut->pFuncs = &ucstrFuncs; 2613 ut->context = s; 2614 ut->providerProperties = I32_FLAG(UTEXT_PROVIDER_STABLE_CHUNKS); 2615 if (length==-1) { 2616 ut->providerProperties |= I32_FLAG(UTEXT_PROVIDER_LENGTH_IS_EXPENSIVE); 2617 } 2618 ut->a = length; 2619 ut->chunkContents = s; 2620 ut->chunkNativeStart = 0; 2621 ut->chunkNativeLimit = length>=0? length : 0; 2622 ut->chunkLength = (int32_t)ut->chunkNativeLimit; 2623 ut->chunkOffset = 0; 2624 ut->nativeIndexingLimit = ut->chunkLength; 2625 } 2626 return ut; 2627 } 2628 2629 2630 //------------------------------------------------------------------------------ 2631 // 2632 // UText implementation for text from ICU CharacterIterators 2633 // 2634 // Use of UText data members: 2635 // context pointer to the CharacterIterator 2636 // a length of the full text. 2637 // p pointer to buffer 1 2638 // b start index of local buffer 1 contents 2639 // q pointer to buffer 2 2640 // c start index of local buffer 2 contents 2641 // r pointer to the character iterator if the UText owns it. 2642 // Null otherwise. 2643 // 2644 //------------------------------------------------------------------------------ 2645 #define CIBufSize 16 2646 2647 U_CDECL_BEGIN 2648 static void U_CALLCONV 2649 charIterTextClose(UText *ut) { 2650 // Most of the work of close is done by the generic UText framework close. 2651 // All that needs to be done here is delete the CharacterIterator if the UText 2652 // owns it. This occurs if the UText was created by cloning. 2653 CharacterIterator *ci = (CharacterIterator *)ut->r; 2654 delete ci; 2655 ut->r = NULL; 2656 } 2657 2658 static int64_t U_CALLCONV 2659 charIterTextLength(UText *ut) { 2660 return (int32_t)ut->a; 2661 } 2662 2663 static UBool U_CALLCONV 2664 charIterTextAccess(UText *ut, int64_t index, UBool forward) { 2665 CharacterIterator *ci = (CharacterIterator *)ut->context; 2666 2667 int32_t clippedIndex = (int32_t)index; 2668 if (clippedIndex<0) { 2669 clippedIndex=0; 2670 } else if (clippedIndex>=ut->a) { 2671 clippedIndex=(int32_t)ut->a; 2672 } 2673 int32_t neededIndex = clippedIndex; 2674 if (!forward && neededIndex>0) { 2675 // reverse iteration, want the position just before what was asked for. 2676 neededIndex--; 2677 } else if (forward && neededIndex==ut->a && neededIndex>0) { 2678 // Forward iteration, don't ask for something past the end of the text. 2679 neededIndex--; 2680 } 2681 2682 // Find the native index of the start of the buffer containing what we want. 2683 neededIndex -= neededIndex % CIBufSize; 2684 2685 UChar *buf = NULL; 2686 UBool needChunkSetup = TRUE; 2687 int i; 2688 if (ut->chunkNativeStart == neededIndex) { 2689 // The buffer we want is already the current chunk. 2690 needChunkSetup = FALSE; 2691 } else if (ut->b == neededIndex) { 2692 // The first buffer (buffer p) has what we need. 2693 buf = (UChar *)ut->p; 2694 } else if (ut->c == neededIndex) { 2695 // The second buffer (buffer q) has what we need. 2696 buf = (UChar *)ut->q; 2697 } else { 2698 // Neither buffer already has what we need. 2699 // Load new data from the character iterator. 2700 // Use the buf that is not the current buffer. 2701 buf = (UChar *)ut->p; 2702 if (ut->p == ut->chunkContents) { 2703 buf = (UChar *)ut->q; 2704 } 2705 ci->setIndex(neededIndex); 2706 for (i=0; i<CIBufSize; i++) { 2707 buf[i] = ci->nextPostInc(); 2708 if (i+neededIndex > ut->a) { 2709 break; 2710 } 2711 } 2712 } 2713 2714 // We have a buffer with the data we need. 2715 // Set it up as the current chunk, if it wasn't already. 2716 if (needChunkSetup) { 2717 ut->chunkContents = buf; 2718 ut->chunkLength = CIBufSize; 2719 ut->chunkNativeStart = neededIndex; 2720 ut->chunkNativeLimit = neededIndex + CIBufSize; 2721 if (ut->chunkNativeLimit > ut->a) { 2722 ut->chunkNativeLimit = ut->a; 2723 ut->chunkLength = (int32_t)(ut->chunkNativeLimit)-(int32_t)(ut->chunkNativeStart); 2724 } 2725 ut->nativeIndexingLimit = ut->chunkLength; 2726 U_ASSERT(ut->chunkOffset>=0 && ut->chunkOffset<=CIBufSize); 2727 } 2728 ut->chunkOffset = clippedIndex - (int32_t)ut->chunkNativeStart; 2729 UBool success = (forward? ut->chunkOffset<ut->chunkLength : ut->chunkOffset>0); 2730 return success; 2731 } 2732 2733 static UText * U_CALLCONV 2734 charIterTextClone(UText *dest, const UText *src, UBool deep, UErrorCode * status) { 2735 if (U_FAILURE(*status)) { 2736 return NULL; 2737 } 2738 2739 if (deep) { 2740 // There is no CharacterIterator API for cloning the underlying text storage. 2741 *status = U_UNSUPPORTED_ERROR; 2742 return NULL; 2743 } else { 2744 CharacterIterator *srcCI =(CharacterIterator *)src->context; 2745 srcCI = srcCI->clone(); 2746 dest = utext_openCharacterIterator(dest, srcCI, status); 2747 if (U_FAILURE(*status)) { 2748 return dest; 2749 } 2750 // cast off const on getNativeIndex. 2751 // For CharacterIterator based UTexts, this is safe, the operation is const. 2752 int64_t ix = utext_getNativeIndex((UText *)src); 2753 utext_setNativeIndex(dest, ix); 2754 dest->r = srcCI; // flags that this UText owns the CharacterIterator 2755 } 2756 return dest; 2757 } 2758 2759 static int32_t U_CALLCONV 2760 charIterTextExtract(UText *ut, 2761 int64_t start, int64_t limit, 2762 UChar *dest, int32_t destCapacity, 2763 UErrorCode *status) 2764 { 2765 if(U_FAILURE(*status)) { 2766 return 0; 2767 } 2768 if(destCapacity<0 || (dest==NULL && destCapacity>0) || start>limit) { 2769 *status=U_ILLEGAL_ARGUMENT_ERROR; 2770 return 0; 2771 } 2772 int32_t length = (int32_t)ut->a; 2773 int32_t start32 = pinIndex(start, length); 2774 int32_t limit32 = pinIndex(limit, length); 2775 int32_t desti = 0; 2776 int32_t srci; 2777 int32_t copyLimit; 2778 2779 CharacterIterator *ci = (CharacterIterator *)ut->context; 2780 ci->setIndex32(start32); // Moves ix to lead of surrogate pair, if needed. 2781 srci = ci->getIndex(); 2782 copyLimit = srci; 2783 while (srci<limit32) { 2784 UChar32 c = ci->next32PostInc(); 2785 int32_t len = U16_LENGTH(c); 2786 U_ASSERT(desti+len>0); /* to ensure desti+len never exceeds MAX_INT32, which must not happen logically */ 2787 if (desti+len <= destCapacity) { 2788 U16_APPEND_UNSAFE(dest, desti, c); 2789 copyLimit = srci+len; 2790 } else { 2791 desti += len; 2792 *status = U_BUFFER_OVERFLOW_ERROR; 2793 } 2794 srci += len; 2795 } 2796 2797 charIterTextAccess(ut, copyLimit, TRUE); 2798 2799 u_terminateUChars(dest, destCapacity, desti, status); 2800 return desti; 2801 } 2802 2803 static const struct UTextFuncs charIterFuncs = 2804 { 2805 sizeof(UTextFuncs), 2806 0, 0, 0, // Reserved alignment padding 2807 charIterTextClone, 2808 charIterTextLength, 2809 charIterTextAccess, 2810 charIterTextExtract, 2811 NULL, // Replace 2812 NULL, // Copy 2813 NULL, // MapOffsetToNative, 2814 NULL, // MapIndexToUTF16, 2815 charIterTextClose, 2816 NULL, // spare 1 2817 NULL, // spare 2 2818 NULL // spare 3 2819 }; 2820 U_CDECL_END 2821 2822 2823 U_CAPI UText * U_EXPORT2 2824 utext_openCharacterIterator(UText *ut, CharacterIterator *ci, UErrorCode *status) { 2825 if (U_FAILURE(*status)) { 2826 return NULL; 2827 } 2828 2829 if (ci->startIndex() > 0) { 2830 // No support for CharacterIterators that do not start indexing from zero. 2831 *status = U_UNSUPPORTED_ERROR; 2832 return NULL; 2833 } 2834 2835 // Extra space in UText for 2 buffers of CIBufSize UChars each. 2836 int32_t extraSpace = 2 * CIBufSize * sizeof(UChar); 2837 ut = utext_setup(ut, extraSpace, status); 2838 if (U_SUCCESS(*status)) { 2839 ut->pFuncs = &charIterFuncs; 2840 ut->context = ci; 2841 ut->providerProperties = 0; 2842 ut->a = ci->endIndex(); // Length of text 2843 ut->p = ut->pExtra; // First buffer 2844 ut->b = -1; // Native index of first buffer contents 2845 ut->q = (UChar*)ut->pExtra+CIBufSize; // Second buffer 2846 ut->c = -1; // Native index of second buffer contents 2847 2848 // Initialize current chunk contents to be empty. 2849 // First access will fault something in. 2850 // Note: The initial nativeStart and chunkOffset must sum to zero 2851 // so that getNativeIndex() will correctly compute to zero 2852 // if no call to Access() has ever been made. They can't be both 2853 // zero without Access() thinking that the chunk is valid. 2854 ut->chunkContents = (UChar *)ut->p; 2855 ut->chunkNativeStart = -1; 2856 ut->chunkOffset = 1; 2857 ut->chunkNativeLimit = 0; 2858 ut->chunkLength = 0; 2859 ut->nativeIndexingLimit = ut->chunkOffset; // enables native indexing 2860 } 2861 return ut; 2862 } 2863