1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ******************************************************************************* 5 * 6 * Copyright (C) 2009-2015, International Business Machines 7 * Corporation and others. All Rights Reserved. 8 * 9 ******************************************************************************* 10 * file name: unorm2.h 11 * encoding: UTF-8 12 * tab size: 8 (not used) 13 * indentation:4 14 * 15 * created on: 2009dec15 16 * created by: Markus W. Scherer 17 */ 18 19 #ifndef __UNORM2_H__ 20 #define __UNORM2_H__ 21 22 /** 23 * \file 24 * \brief C API: New API for Unicode Normalization. 25 * 26 * Unicode normalization functionality for standard Unicode normalization or 27 * for using custom mapping tables. 28 * All instances of UNormalizer2 are unmodifiable/immutable. 29 * Instances returned by unorm2_getInstance() are singletons that must not be deleted by the caller. 30 * For more details see the Normalizer2 C++ class. 31 */ 32 33 #include "unicode/utypes.h" 34 #include "unicode/stringoptions.h" 35 #include "unicode/uset.h" 36 37 #if U_SHOW_CPLUSPLUS_API 38 #include "unicode/localpointer.h" 39 #endif // U_SHOW_CPLUSPLUS_API 40 41 /** 42 * Constants for normalization modes. 43 * For details about standard Unicode normalization forms 44 * and about the algorithms which are also used with custom mapping tables 45 * see http://www.unicode.org/unicode/reports/tr15/ 46 * @stable ICU 4.4 47 */ 48 typedef enum { 49 /** 50 * Decomposition followed by composition. 51 * Same as standard NFC when using an "nfc" instance. 52 * Same as standard NFKC when using an "nfkc" instance. 53 * For details about standard Unicode normalization forms 54 * see http://www.unicode.org/unicode/reports/tr15/ 55 * @stable ICU 4.4 56 */ 57 UNORM2_COMPOSE, 58 /** 59 * Map, and reorder canonically. 60 * Same as standard NFD when using an "nfc" instance. 61 * Same as standard NFKD when using an "nfkc" instance. 62 * For details about standard Unicode normalization forms 63 * see http://www.unicode.org/unicode/reports/tr15/ 64 * @stable ICU 4.4 65 */ 66 UNORM2_DECOMPOSE, 67 /** 68 * "Fast C or D" form. 69 * If a string is in this form, then further decomposition <i>without reordering</i> 70 * would yield the same form as DECOMPOSE. 71 * Text in "Fast C or D" form can be processed efficiently with data tables 72 * that are "canonically closed", that is, that provide equivalent data for 73 * equivalent text, without having to be fully normalized. 74 * Not a standard Unicode normalization form. 75 * Not a unique form: Different FCD strings can be canonically equivalent. 76 * For details see http://www.unicode.org/notes/tn5/#FCD 77 * @stable ICU 4.4 78 */ 79 UNORM2_FCD, 80 /** 81 * Compose only contiguously. 82 * Also known as "FCC" or "Fast C Contiguous". 83 * The result will often but not always be in NFC. 84 * The result will conform to FCD which is useful for processing. 85 * Not a standard Unicode normalization form. 86 * For details see http://www.unicode.org/notes/tn5/#FCC 87 * @stable ICU 4.4 88 */ 89 UNORM2_COMPOSE_CONTIGUOUS 90 } UNormalization2Mode; 91 92 /** 93 * Result values for normalization quick check functions. 94 * For details see http://www.unicode.org/reports/tr15/#Detecting_Normalization_Forms 95 * @stable ICU 2.0 96 */ 97 typedef enum UNormalizationCheckResult { 98 /** 99 * The input string is not in the normalization form. 100 * @stable ICU 2.0 101 */ 102 UNORM_NO, 103 /** 104 * The input string is in the normalization form. 105 * @stable ICU 2.0 106 */ 107 UNORM_YES, 108 /** 109 * The input string may or may not be in the normalization form. 110 * This value is only returned for composition forms like NFC and FCC, 111 * when a backward-combining character is found for which the surrounding text 112 * would have to be analyzed further. 113 * @stable ICU 2.0 114 */ 115 UNORM_MAYBE 116 } UNormalizationCheckResult; 117 118 /** 119 * Opaque C service object type for the new normalization API. 120 * @stable ICU 4.4 121 */ 122 struct UNormalizer2; 123 typedef struct UNormalizer2 UNormalizer2; /**< C typedef for struct UNormalizer2. @stable ICU 4.4 */ 124 125 #if !UCONFIG_NO_NORMALIZATION 126 127 /** 128 * Returns a UNormalizer2 instance for Unicode NFC normalization. 129 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_COMPOSE, pErrorCode). 130 * Returns an unmodifiable singleton instance. Do not delete it. 131 * @param pErrorCode Standard ICU error code. Its input value must 132 * pass the U_SUCCESS() test, or else the function returns 133 * immediately. Check for U_FAILURE() on output or use with 134 * function chaining. (See User Guide for details.) 135 * @return the requested Normalizer2, if successful 136 * @stable ICU 49 137 */ 138 U_CAPI const UNormalizer2 * U_EXPORT2 139 unorm2_getNFCInstance(UErrorCode *pErrorCode); 140 141 /** 142 * Returns a UNormalizer2 instance for Unicode NFD normalization. 143 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_DECOMPOSE, pErrorCode). 144 * Returns an unmodifiable singleton instance. Do not delete it. 145 * @param pErrorCode Standard ICU error code. Its input value must 146 * pass the U_SUCCESS() test, or else the function returns 147 * immediately. Check for U_FAILURE() on output or use with 148 * function chaining. (See User Guide for details.) 149 * @return the requested Normalizer2, if successful 150 * @stable ICU 49 151 */ 152 U_CAPI const UNormalizer2 * U_EXPORT2 153 unorm2_getNFDInstance(UErrorCode *pErrorCode); 154 155 /** 156 * Returns a UNormalizer2 instance for Unicode NFKC normalization. 157 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_COMPOSE, pErrorCode). 158 * Returns an unmodifiable singleton instance. Do not delete it. 159 * @param pErrorCode Standard ICU error code. Its input value must 160 * pass the U_SUCCESS() test, or else the function returns 161 * immediately. Check for U_FAILURE() on output or use with 162 * function chaining. (See User Guide for details.) 163 * @return the requested Normalizer2, if successful 164 * @stable ICU 49 165 */ 166 U_CAPI const UNormalizer2 * U_EXPORT2 167 unorm2_getNFKCInstance(UErrorCode *pErrorCode); 168 169 /** 170 * Returns a UNormalizer2 instance for Unicode NFKD normalization. 171 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_DECOMPOSE, pErrorCode). 172 * Returns an unmodifiable singleton instance. Do not delete it. 173 * @param pErrorCode Standard ICU error code. Its input value must 174 * pass the U_SUCCESS() test, or else the function returns 175 * immediately. Check for U_FAILURE() on output or use with 176 * function chaining. (See User Guide for details.) 177 * @return the requested Normalizer2, if successful 178 * @stable ICU 49 179 */ 180 U_CAPI const UNormalizer2 * U_EXPORT2 181 unorm2_getNFKDInstance(UErrorCode *pErrorCode); 182 183 /** 184 * Returns a UNormalizer2 instance for Unicode toNFKC_Casefold() normalization 185 * which is equivalent to applying the NFKC_Casefold mappings and then NFC. 186 * See https://www.unicode.org/reports/tr44/#NFKC_Casefold 187 * 188 * Same as unorm2_getInstance(NULL, "nfkc_cf", UNORM2_COMPOSE, pErrorCode). 189 * Returns an unmodifiable singleton instance. Do not delete it. 190 * @param pErrorCode Standard ICU error code. Its input value must 191 * pass the U_SUCCESS() test, or else the function returns 192 * immediately. Check for U_FAILURE() on output or use with 193 * function chaining. (See User Guide for details.) 194 * @return the requested Normalizer2, if successful 195 * @stable ICU 49 196 */ 197 U_CAPI const UNormalizer2 * U_EXPORT2 198 unorm2_getNFKCCasefoldInstance(UErrorCode *pErrorCode); 199 200 /** 201 * Returns a UNormalizer2 instance for a variant of Unicode toNFKC_Casefold() normalization 202 * which is equivalent to applying the NFKC_Simple_Casefold mappings and then NFC. 203 * See https://www.unicode.org/reports/tr44/#NFKC_Simple_Casefold 204 * 205 * Same as unorm2_getInstance(NULL, "nfkc_scf", UNORM2_COMPOSE, pErrorCode). 206 * Returns an unmodifiable singleton instance. Do not delete it. 207 * @param pErrorCode Standard ICU error code. Its input value must 208 * pass the U_SUCCESS() test, or else the function returns 209 * immediately. Check for U_FAILURE() on output or use with 210 * function chaining. (See User Guide for details.) 211 * @return the requested Normalizer2, if successful 212 * @stable ICU 74 213 */ 214 U_CAPI const UNormalizer2 * U_EXPORT2 215 unorm2_getNFKCSimpleCasefoldInstance(UErrorCode *pErrorCode); 216 217 /** 218 * Returns a UNormalizer2 instance which uses the specified data file 219 * (packageName/name similar to ucnv_openPackage() and ures_open()/ResourceBundle) 220 * and which composes or decomposes text according to the specified mode. 221 * Returns an unmodifiable singleton instance. Do not delete it. 222 * 223 * Use packageName=NULL for data files that are part of ICU's own data. 224 * Use name="nfc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFC/NFD. 225 * Use name="nfkc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFKC/NFKD. 226 * Use name="nfkc_cf" and UNORM2_COMPOSE for Unicode standard NFKC_CF=NFKC_Casefold. 227 * 228 * @param packageName NULL for ICU built-in data, otherwise application data package name 229 * @param name "nfc" or "nfkc" or "nfkc_cf" or "nfkc_scf" or name of custom data file 230 * @param mode normalization mode (compose or decompose etc.) 231 * @param pErrorCode Standard ICU error code. Its input value must 232 * pass the U_SUCCESS() test, or else the function returns 233 * immediately. Check for U_FAILURE() on output or use with 234 * function chaining. (See User Guide for details.) 235 * @return the requested UNormalizer2, if successful 236 * @stable ICU 4.4 237 */ 238 U_CAPI const UNormalizer2 * U_EXPORT2 239 unorm2_getInstance(const char *packageName, 240 const char *name, 241 UNormalization2Mode mode, 242 UErrorCode *pErrorCode); 243 244 /** 245 * Constructs a filtered normalizer wrapping any UNormalizer2 instance 246 * and a filter set. 247 * Both are aliased and must not be modified or deleted while this object 248 * is used. 249 * The filter set should be frozen; otherwise the performance will suffer greatly. 250 * @param norm2 wrapped UNormalizer2 instance 251 * @param filterSet USet which determines the characters to be normalized 252 * @param pErrorCode Standard ICU error code. Its input value must 253 * pass the U_SUCCESS() test, or else the function returns 254 * immediately. Check for U_FAILURE() on output or use with 255 * function chaining. (See User Guide for details.) 256 * @return the requested UNormalizer2, if successful 257 * @stable ICU 4.4 258 */ 259 U_CAPI UNormalizer2 * U_EXPORT2 260 unorm2_openFiltered(const UNormalizer2 *norm2, const USet *filterSet, UErrorCode *pErrorCode); 261 262 /** 263 * Closes a UNormalizer2 instance from unorm2_openFiltered(). 264 * Do not close instances from unorm2_getInstance()! 265 * @param norm2 UNormalizer2 instance to be closed 266 * @stable ICU 4.4 267 */ 268 U_CAPI void U_EXPORT2 269 unorm2_close(UNormalizer2 *norm2); 270 271 #if U_SHOW_CPLUSPLUS_API 272 273 U_NAMESPACE_BEGIN 274 275 /** 276 * \class LocalUNormalizer2Pointer 277 * "Smart pointer" class, closes a UNormalizer2 via unorm2_close(). 278 * For most methods see the LocalPointerBase base class. 279 * 280 * @see LocalPointerBase 281 * @see LocalPointer 282 * @stable ICU 4.4 283 */ 284 U_DEFINE_LOCAL_OPEN_POINTER(LocalUNormalizer2Pointer, UNormalizer2, unorm2_close); 285 286 U_NAMESPACE_END 287 288 #endif 289 290 /** 291 * Writes the normalized form of the source string to the destination string 292 * (replacing its contents) and returns the length of the destination string. 293 * The source and destination strings must be different buffers. 294 * @param norm2 UNormalizer2 instance 295 * @param src source string 296 * @param length length of the source string, or -1 if NUL-terminated 297 * @param dest destination string; its contents is replaced with normalized src 298 * @param capacity number of UChars that can be written to dest 299 * @param pErrorCode Standard ICU error code. Its input value must 300 * pass the U_SUCCESS() test, or else the function returns 301 * immediately. Check for U_FAILURE() on output or use with 302 * function chaining. (See User Guide for details.) 303 * @return dest 304 * @stable ICU 4.4 305 */ 306 U_CAPI int32_t U_EXPORT2 307 unorm2_normalize(const UNormalizer2 *norm2, 308 const UChar *src, int32_t length, 309 UChar *dest, int32_t capacity, 310 UErrorCode *pErrorCode); 311 /** 312 * Appends the normalized form of the second string to the first string 313 * (merging them at the boundary) and returns the length of the first string. 314 * The result is normalized if the first string was normalized. 315 * The first and second strings must be different buffers. 316 * @param norm2 UNormalizer2 instance 317 * @param first string, should be normalized 318 * @param firstLength length of the first string, or -1 if NUL-terminated 319 * @param firstCapacity number of UChars that can be written to first 320 * @param second string, will be normalized 321 * @param secondLength length of the source string, or -1 if NUL-terminated 322 * @param pErrorCode Standard ICU error code. Its input value must 323 * pass the U_SUCCESS() test, or else the function returns 324 * immediately. Check for U_FAILURE() on output or use with 325 * function chaining. (See User Guide for details.) 326 * @return first 327 * @stable ICU 4.4 328 */ 329 U_CAPI int32_t U_EXPORT2 330 unorm2_normalizeSecondAndAppend(const UNormalizer2 *norm2, 331 UChar *first, int32_t firstLength, int32_t firstCapacity, 332 const UChar *second, int32_t secondLength, 333 UErrorCode *pErrorCode); 334 /** 335 * Appends the second string to the first string 336 * (merging them at the boundary) and returns the length of the first string. 337 * The result is normalized if both the strings were normalized. 338 * The first and second strings must be different buffers. 339 * @param norm2 UNormalizer2 instance 340 * @param first string, should be normalized 341 * @param firstLength length of the first string, or -1 if NUL-terminated 342 * @param firstCapacity number of UChars that can be written to first 343 * @param second string, should be normalized 344 * @param secondLength length of the source string, or -1 if NUL-terminated 345 * @param pErrorCode Standard ICU error code. Its input value must 346 * pass the U_SUCCESS() test, or else the function returns 347 * immediately. Check for U_FAILURE() on output or use with 348 * function chaining. (See User Guide for details.) 349 * @return first 350 * @stable ICU 4.4 351 */ 352 U_CAPI int32_t U_EXPORT2 353 unorm2_append(const UNormalizer2 *norm2, 354 UChar *first, int32_t firstLength, int32_t firstCapacity, 355 const UChar *second, int32_t secondLength, 356 UErrorCode *pErrorCode); 357 358 /** 359 * Gets the decomposition mapping of c. 360 * Roughly equivalent to normalizing the String form of c 361 * on a UNORM2_DECOMPOSE UNormalizer2 instance, but much faster, and except that this function 362 * returns a negative value and does not write a string 363 * if c does not have a decomposition mapping in this instance's data. 364 * This function is independent of the mode of the UNormalizer2. 365 * @param norm2 UNormalizer2 instance 366 * @param c code point 367 * @param decomposition String buffer which will be set to c's 368 * decomposition mapping, if there is one. 369 * @param capacity number of UChars that can be written to decomposition 370 * @param pErrorCode Standard ICU error code. Its input value must 371 * pass the U_SUCCESS() test, or else the function returns 372 * immediately. Check for U_FAILURE() on output or use with 373 * function chaining. (See User Guide for details.) 374 * @return the non-negative length of c's decomposition, if there is one; otherwise a negative value 375 * @stable ICU 4.6 376 */ 377 U_CAPI int32_t U_EXPORT2 378 unorm2_getDecomposition(const UNormalizer2 *norm2, 379 UChar32 c, UChar *decomposition, int32_t capacity, 380 UErrorCode *pErrorCode); 381 382 /** 383 * Gets the raw decomposition mapping of c. 384 * 385 * This is similar to the unorm2_getDecomposition() function but returns the 386 * raw decomposition mapping as specified in UnicodeData.txt or 387 * (for custom data) in the mapping files processed by the gennorm2 tool. 388 * By contrast, unorm2_getDecomposition() returns the processed, 389 * recursively-decomposed version of this mapping. 390 * 391 * When used on a standard NFKC Normalizer2 instance, 392 * unorm2_getRawDecomposition() returns the Unicode Decomposition_Mapping (dm) property. 393 * 394 * When used on a standard NFC Normalizer2 instance, 395 * it returns the Decomposition_Mapping only if the Decomposition_Type (dt) is Canonical (Can); 396 * in this case, the result contains either one or two code points (=1..4 UChars). 397 * 398 * This function is independent of the mode of the UNormalizer2. 399 * @param norm2 UNormalizer2 instance 400 * @param c code point 401 * @param decomposition String buffer which will be set to c's 402 * raw decomposition mapping, if there is one. 403 * @param capacity number of UChars that can be written to decomposition 404 * @param pErrorCode Standard ICU error code. Its input value must 405 * pass the U_SUCCESS() test, or else the function returns 406 * immediately. Check for U_FAILURE() on output or use with 407 * function chaining. (See User Guide for details.) 408 * @return the non-negative length of c's raw decomposition, if there is one; otherwise a negative value 409 * @stable ICU 49 410 */ 411 U_CAPI int32_t U_EXPORT2 412 unorm2_getRawDecomposition(const UNormalizer2 *norm2, 413 UChar32 c, UChar *decomposition, int32_t capacity, 414 UErrorCode *pErrorCode); 415 416 /** 417 * Performs pairwise composition of a & b and returns the composite if there is one. 418 * 419 * Returns a composite code point c only if c has a two-way mapping to a+b. 420 * In standard Unicode normalization, this means that 421 * c has a canonical decomposition to a+b 422 * and c does not have the Full_Composition_Exclusion property. 423 * 424 * This function is independent of the mode of the UNormalizer2. 425 * @param norm2 UNormalizer2 instance 426 * @param a A (normalization starter) code point. 427 * @param b Another code point. 428 * @return The non-negative composite code point if there is one; otherwise a negative value. 429 * @stable ICU 49 430 */ 431 U_CAPI UChar32 U_EXPORT2 432 unorm2_composePair(const UNormalizer2 *norm2, UChar32 a, UChar32 b); 433 434 /** 435 * Gets the combining class of c. 436 * The default implementation returns 0 437 * but all standard implementations return the Unicode Canonical_Combining_Class value. 438 * @param norm2 UNormalizer2 instance 439 * @param c code point 440 * @return c's combining class 441 * @stable ICU 49 442 */ 443 U_CAPI uint8_t U_EXPORT2 444 unorm2_getCombiningClass(const UNormalizer2 *norm2, UChar32 c); 445 446 /** 447 * Tests if the string is normalized. 448 * Internally, in cases where the quickCheck() method would return "maybe" 449 * (which is only possible for the two COMPOSE modes) this method 450 * resolves to "yes" or "no" to provide a definitive result, 451 * at the cost of doing more work in those cases. 452 * @param norm2 UNormalizer2 instance 453 * @param s input string 454 * @param length length of the string, or -1 if NUL-terminated 455 * @param pErrorCode Standard ICU error code. Its input value must 456 * pass the U_SUCCESS() test, or else the function returns 457 * immediately. Check for U_FAILURE() on output or use with 458 * function chaining. (See User Guide for details.) 459 * @return true if s is normalized 460 * @stable ICU 4.4 461 */ 462 U_CAPI UBool U_EXPORT2 463 unorm2_isNormalized(const UNormalizer2 *norm2, 464 const UChar *s, int32_t length, 465 UErrorCode *pErrorCode); 466 467 /** 468 * Tests if the string is normalized. 469 * For the two COMPOSE modes, the result could be "maybe" in cases that 470 * would take a little more work to resolve definitively. 471 * Use spanQuickCheckYes() and normalizeSecondAndAppend() for a faster 472 * combination of quick check + normalization, to avoid 473 * re-checking the "yes" prefix. 474 * @param norm2 UNormalizer2 instance 475 * @param s input string 476 * @param length length of the string, or -1 if NUL-terminated 477 * @param pErrorCode Standard ICU error code. Its input value must 478 * pass the U_SUCCESS() test, or else the function returns 479 * immediately. Check for U_FAILURE() on output or use with 480 * function chaining. (See User Guide for details.) 481 * @return UNormalizationCheckResult 482 * @stable ICU 4.4 483 */ 484 U_CAPI UNormalizationCheckResult U_EXPORT2 485 unorm2_quickCheck(const UNormalizer2 *norm2, 486 const UChar *s, int32_t length, 487 UErrorCode *pErrorCode); 488 489 /** 490 * Returns the end of the normalized substring of the input string. 491 * In other words, with <code>end=spanQuickCheckYes(s, ec);</code> 492 * the substring <code>UnicodeString(s, 0, end)</code> 493 * will pass the quick check with a "yes" result. 494 * 495 * The returned end index is usually one or more characters before the 496 * "no" or "maybe" character: The end index is at a normalization boundary. 497 * (See the class documentation for more about normalization boundaries.) 498 * 499 * When the goal is a normalized string and most input strings are expected 500 * to be normalized already, then call this method, 501 * and if it returns a prefix shorter than the input string, 502 * copy that prefix and use normalizeSecondAndAppend() for the remainder. 503 * @param norm2 UNormalizer2 instance 504 * @param s input string 505 * @param length length of the string, or -1 if NUL-terminated 506 * @param pErrorCode Standard ICU error code. Its input value must 507 * pass the U_SUCCESS() test, or else the function returns 508 * immediately. Check for U_FAILURE() on output or use with 509 * function chaining. (See User Guide for details.) 510 * @return "yes" span end index 511 * @stable ICU 4.4 512 */ 513 U_CAPI int32_t U_EXPORT2 514 unorm2_spanQuickCheckYes(const UNormalizer2 *norm2, 515 const UChar *s, int32_t length, 516 UErrorCode *pErrorCode); 517 518 /** 519 * Tests if the character always has a normalization boundary before it, 520 * regardless of context. 521 * For details see the Normalizer2 base class documentation. 522 * @param norm2 UNormalizer2 instance 523 * @param c character to test 524 * @return true if c has a normalization boundary before it 525 * @stable ICU 4.4 526 */ 527 U_CAPI UBool U_EXPORT2 528 unorm2_hasBoundaryBefore(const UNormalizer2 *norm2, UChar32 c); 529 530 /** 531 * Tests if the character always has a normalization boundary after it, 532 * regardless of context. 533 * For details see the Normalizer2 base class documentation. 534 * @param norm2 UNormalizer2 instance 535 * @param c character to test 536 * @return true if c has a normalization boundary after it 537 * @stable ICU 4.4 538 */ 539 U_CAPI UBool U_EXPORT2 540 unorm2_hasBoundaryAfter(const UNormalizer2 *norm2, UChar32 c); 541 542 /** 543 * Tests if the character is normalization-inert. 544 * For details see the Normalizer2 base class documentation. 545 * @param norm2 UNormalizer2 instance 546 * @param c character to test 547 * @return true if c is normalization-inert 548 * @stable ICU 4.4 549 */ 550 U_CAPI UBool U_EXPORT2 551 unorm2_isInert(const UNormalizer2 *norm2, UChar32 c); 552 553 /** 554 * Compares two strings for canonical equivalence. 555 * Further options include case-insensitive comparison and 556 * code point order (as opposed to code unit order). 557 * 558 * Canonical equivalence between two strings is defined as their normalized 559 * forms (NFD or NFC) being identical. 560 * This function compares strings incrementally instead of normalizing 561 * (and optionally case-folding) both strings entirely, 562 * improving performance significantly. 563 * 564 * Bulk normalization is only necessary if the strings do not fulfill the FCD 565 * conditions. Only in this case, and only if the strings are relatively long, 566 * is memory allocated temporarily. 567 * For FCD strings and short non-FCD strings there is no memory allocation. 568 * 569 * Semantically, this is equivalent to 570 * strcmp[CodePointOrder](NFD(foldCase(NFD(s1))), NFD(foldCase(NFD(s2)))) 571 * where code point order and foldCase are all optional. 572 * 573 * UAX 21 2.5 Caseless Matching specifies that for a canonical caseless match 574 * the case folding must be performed first, then the normalization. 575 * 576 * @param s1 First source string. 577 * @param length1 Length of first source string, or -1 if NUL-terminated. 578 * 579 * @param s2 Second source string. 580 * @param length2 Length of second source string, or -1 if NUL-terminated. 581 * 582 * @param options A bit set of options: 583 * - U_FOLD_CASE_DEFAULT or 0 is used for default options: 584 * Case-sensitive comparison in code unit order, and the input strings 585 * are quick-checked for FCD. 586 * 587 * - UNORM_INPUT_IS_FCD 588 * Set if the caller knows that both s1 and s2 fulfill the FCD conditions. 589 * If not set, the function will quickCheck for FCD 590 * and normalize if necessary. 591 * 592 * - U_COMPARE_CODE_POINT_ORDER 593 * Set to choose code point order instead of code unit order 594 * (see u_strCompare for details). 595 * 596 * - U_COMPARE_IGNORE_CASE 597 * Set to compare strings case-insensitively using case folding, 598 * instead of case-sensitively. 599 * If set, then the following case folding options are used. 600 * 601 * - Options as used with case-insensitive comparisons, currently: 602 * 603 * - U_FOLD_CASE_EXCLUDE_SPECIAL_I 604 * (see u_strCaseCompare for details) 605 * 606 * - regular normalization options shifted left by UNORM_COMPARE_NORM_OPTIONS_SHIFT 607 * 608 * @param pErrorCode ICU error code in/out parameter. 609 * Must fulfill U_SUCCESS before the function call. 610 * @return <0 or 0 or >0 as usual for string comparisons 611 * 612 * @see unorm_normalize 613 * @see UNORM_FCD 614 * @see u_strCompare 615 * @see u_strCaseCompare 616 * 617 * @stable ICU 2.2 618 */ 619 U_CAPI int32_t U_EXPORT2 620 unorm_compare(const UChar *s1, int32_t length1, 621 const UChar *s2, int32_t length2, 622 uint32_t options, 623 UErrorCode *pErrorCode); 624 625 #endif /* !UCONFIG_NO_NORMALIZATION */ 626 #endif /* __UNORM2_H__ */ 627