icuSources/common/unicode/unorm2.h

   1 /*
   2 *******************************************************************************
   3 *
   4 *   Copyright (C) 2009-2015, International Business Machines
   5 *   Corporation and others.  All Rights Reserved.
   6 *
   7 *******************************************************************************
   8 *   file name:  unorm2.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 2009dec15
  14 *   created by: Markus W. Scherer
  15 */
  16
  17 #ifndef __UNORM2_H__
  18 #define __UNORM2_H__
  19
  20 /**
  21  * \file
  22  * \brief C API: New API for Unicode Normalization.
  23  *
  24  * Unicode normalization functionality for standard Unicode normalization or
  25  * for using custom mapping tables.
  26  * All instances of UNormalizer2 are unmodifiable/immutable.
  27  * Instances returned by unorm2_getInstance() are singletons that must not be deleted by the caller.
  28  * For more details see the Normalizer2 C++ class.
  29  */
  30
  31 #include "unicode/utypes.h"
  32 #include "unicode/localpointer.h"
  33 #include "unicode/uset.h"
  34
  35 /**
  36  * Constants for normalization modes.
  37  * For details about standard Unicode normalization forms
  38  * and about the algorithms which are also used with custom mapping tables
  39  * see http://www.unicode.org/unicode/reports/tr15/
  40  * @stable ICU 4.4
  41  */
  42 typedef enum {
  43     /**
  44      * Decomposition followed by composition.
  45      * Same as standard NFC when using an "nfc" instance.
  46      * Same as standard NFKC when using an "nfkc" instance.
  47      * For details about standard Unicode normalization forms
  48      * see http://www.unicode.org/unicode/reports/tr15/
  49      * @stable ICU 4.4
  50      */
  51     UNORM2_COMPOSE,
  52     /**
  53      * Map, and reorder canonically.
  54      * Same as standard NFD when using an "nfc" instance.
  55      * Same as standard NFKD when using an "nfkc" instance.
  56      * For details about standard Unicode normalization forms
  57      * see http://www.unicode.org/unicode/reports/tr15/
  58      * @stable ICU 4.4
  59      */
  60     UNORM2_DECOMPOSE,
  61     /**
  62      * "Fast C or D" form.
  63      * If a string is in this form, then further decomposition <i>without reordering</i>
  64      * would yield the same form as DECOMPOSE.
  65      * Text in "Fast C or D" form can be processed efficiently with data tables
  66      * that are "canonically closed", that is, that provide equivalent data for
  67      * equivalent text, without having to be fully normalized.
  68      * Not a standard Unicode normalization form.
  69      * Not a unique form: Different FCD strings can be canonically equivalent.
  70      * For details see http://www.unicode.org/notes/tn5/#FCD
  71      * @stable ICU 4.4
  72      */
  73     UNORM2_FCD,
  74     /**
  75      * Compose only contiguously.
  76      * Also known as "FCC" or "Fast C Contiguous".
  77      * The result will often but not always be in NFC.
  78      * The result will conform to FCD which is useful for processing.
  79      * Not a standard Unicode normalization form.
  80      * For details see http://www.unicode.org/notes/tn5/#FCC
  81      * @stable ICU 4.4
  82      */
  83     UNORM2_COMPOSE_CONTIGUOUS
  84 } UNormalization2Mode;
  85
  86 /**
  87  * Result values for normalization quick check functions.
  88  * For details see http://www.unicode.org/reports/tr15/#Detecting_Normalization_Forms
  89  * @stable ICU 2.0
  90  */
  91 typedef enum UNormalizationCheckResult {
  92   /**
  93    * The input string is not in the normalization form.
  94    * @stable ICU 2.0
  95    */
  96   UNORM_NO,
  97   /**
  98    * The input string is in the normalization form.
  99    * @stable ICU 2.0
 100    */
 101   UNORM_YES,
 102   /**
 103    * The input string may or may not be in the normalization form.
 104    * This value is only returned for composition forms like NFC and FCC,
 105    * when a backward-combining character is found for which the surrounding text
 106    * would have to be analyzed further.
 107    * @stable ICU 2.0
 108    */
 109   UNORM_MAYBE
 110 } UNormalizationCheckResult;
 111
 112 /**
 113  * Opaque C service object type for the new normalization API.
 114  * @stable ICU 4.4
 115  */
 116 struct UNormalizer2;
 117 typedef struct UNormalizer2 UNormalizer2;  /**< C typedef for struct UNormalizer2. @stable ICU 4.4 */
 118
 119 #if !UCONFIG_NO_NORMALIZATION
 120
 121 /**
 122  * Returns a UNormalizer2 instance for Unicode NFC normalization.
 123  * Same as unorm2_getInstance(NULL, "nfc", UNORM2_COMPOSE, pErrorCode).
 124  * Returns an unmodifiable singleton instance. Do not delete it.
 125  * @param pErrorCode Standard ICU error code. Its input value must
 126  *                  pass the U_SUCCESS() test, or else the function returns
 127  *                  immediately. Check for U_FAILURE() on output or use with
 128  *                  function chaining. (See User Guide for details.)
 129  * @return the requested Normalizer2, if successful
 130  * @stable ICU 49
 131  */
 132 U_STABLE const UNormalizer2 * U_EXPORT2
 133 unorm2_getNFCInstance(UErrorCode *pErrorCode);
 134
 135 /**
 136  * Returns a UNormalizer2 instance for Unicode NFD normalization.
 137  * Same as unorm2_getInstance(NULL, "nfc", UNORM2_DECOMPOSE, pErrorCode).
 138  * Returns an unmodifiable singleton instance. Do not delete it.
 139  * @param pErrorCode Standard ICU error code. Its input value must
 140  *                  pass the U_SUCCESS() test, or else the function returns
 141  *                  immediately. Check for U_FAILURE() on output or use with
 142  *                  function chaining. (See User Guide for details.)
 143  * @return the requested Normalizer2, if successful
 144  * @stable ICU 49
 145  */
 146 U_STABLE const UNormalizer2 * U_EXPORT2
 147 unorm2_getNFDInstance(UErrorCode *pErrorCode);
 148
 149 /**
 150  * Returns a UNormalizer2 instance for Unicode NFKC normalization.
 151  * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_COMPOSE, pErrorCode).
 152  * Returns an unmodifiable singleton instance. Do not delete it.
 153  * @param pErrorCode Standard ICU error code. Its input value must
 154  *                  pass the U_SUCCESS() test, or else the function returns
 155  *                  immediately. Check for U_FAILURE() on output or use with
 156  *                  function chaining. (See User Guide for details.)
 157  * @return the requested Normalizer2, if successful
 158  * @stable ICU 49
 159  */
 160 U_STABLE const UNormalizer2 * U_EXPORT2
 161 unorm2_getNFKCInstance(UErrorCode *pErrorCode);
 162
 163 /**
 164  * Returns a UNormalizer2 instance for Unicode NFKD normalization.
 165  * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_DECOMPOSE, pErrorCode).
 166  * Returns an unmodifiable singleton instance. Do not delete it.
 167  * @param pErrorCode Standard ICU error code. Its input value must
 168  *                  pass the U_SUCCESS() test, or else the function returns
 169  *                  immediately. Check for U_FAILURE() on output or use with
 170  *                  function chaining. (See User Guide for details.)
 171  * @return the requested Normalizer2, if successful
 172  * @stable ICU 49
 173  */
 174 U_STABLE const UNormalizer2 * U_EXPORT2
 175 unorm2_getNFKDInstance(UErrorCode *pErrorCode);
 176
 177 /**
 178  * Returns a UNormalizer2 instance for Unicode NFKC_Casefold normalization.
 179  * Same as unorm2_getInstance(NULL, "nfkc_cf", UNORM2_COMPOSE, pErrorCode).
 180  * Returns an unmodifiable singleton instance. Do not delete it.
 181  * @param pErrorCode Standard ICU error code. Its input value must
 182  *                  pass the U_SUCCESS() test, or else the function returns
 183  *                  immediately. Check for U_FAILURE() on output or use with
 184  *                  function chaining. (See User Guide for details.)
 185  * @return the requested Normalizer2, if successful
 186  * @stable ICU 49
 187  */
 188 U_STABLE const UNormalizer2 * U_EXPORT2
 189 unorm2_getNFKCCasefoldInstance(UErrorCode *pErrorCode);
 190
 191 /**
 192  * Returns a UNormalizer2 instance which uses the specified data file
 193  * (packageName/name similar to ucnv_openPackage() and ures_open()/ResourceBundle)
 194  * and which composes or decomposes text according to the specified mode.
 195  * Returns an unmodifiable singleton instance. Do not delete it.
 196  *
 197  * Use packageName=NULL for data files that are part of ICU's own data.
 198  * Use name="nfc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFC/NFD.
 199  * Use name="nfkc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFKC/NFKD.
 200  * Use name="nfkc_cf" and UNORM2_COMPOSE for Unicode standard NFKC_CF=NFKC_Casefold.
 201  *
 202  * @param packageName NULL for ICU built-in data, otherwise application data package name
 203  * @param name "nfc" or "nfkc" or "nfkc_cf" or name of custom data file
 204  * @param mode normalization mode (compose or decompose etc.)
 205  * @param pErrorCode Standard ICU error code. Its input value must
 206  *                  pass the U_SUCCESS() test, or else the function returns
 207  *                  immediately. Check for U_FAILURE() on output or use with
 208  *                  function chaining. (See User Guide for details.)
 209  * @return the requested UNormalizer2, if successful
 210  * @stable ICU 4.4
 211  */
 212 U_STABLE const UNormalizer2 * U_EXPORT2
 213 unorm2_getInstance(const char *packageName,
 214                    const char *name,
 215                    UNormalization2Mode mode,
 216                    UErrorCode *pErrorCode);
 217
 218 /**
 219  * Constructs a filtered normalizer wrapping any UNormalizer2 instance
 220  * and a filter set.
 221  * Both are aliased and must not be modified or deleted while this object
 222  * is used.
 223  * The filter set should be frozen; otherwise the performance will suffer greatly.
 224  * @param norm2 wrapped UNormalizer2 instance
 225  * @param filterSet USet which determines the characters to be normalized
 226  * @param pErrorCode Standard ICU error code. Its input value must
 227  *                   pass the U_SUCCESS() test, or else the function returns
 228  *                   immediately. Check for U_FAILURE() on output or use with
 229  *                   function chaining. (See User Guide for details.)
 230  * @return the requested UNormalizer2, if successful
 231  * @stable ICU 4.4
 232  */
 233 U_STABLE UNormalizer2 * U_EXPORT2
 234 unorm2_openFiltered(const UNormalizer2 *norm2, const USet *filterSet, UErrorCode *pErrorCode);
 235
 236 /**
 237  * Closes a UNormalizer2 instance from unorm2_openFiltered().
 238  * Do not close instances from unorm2_getInstance()!
 239  * @param norm2 UNormalizer2 instance to be closed
 240  * @stable ICU 4.4
 241  */
 242 U_STABLE void U_EXPORT2
 243 unorm2_close(UNormalizer2 *norm2);
 244
 245 #if U_SHOW_CPLUSPLUS_API
 246
 247 U_NAMESPACE_BEGIN
 248
 249 /**
 250  * \class LocalUNormalizer2Pointer
 251  * "Smart pointer" class, closes a UNormalizer2 via unorm2_close().
 252  * For most methods see the LocalPointerBase base class.
 253  *
 254  * @see LocalPointerBase
 255  * @see LocalPointer
 256  * @stable ICU 4.4
 257  */
 258 U_DEFINE_LOCAL_OPEN_POINTER(LocalUNormalizer2Pointer, UNormalizer2, unorm2_close);
 259
 260 U_NAMESPACE_END
 261
 262 #endif
 263
 264 /**
 265  * Writes the normalized form of the source string to the destination string
 266  * (replacing its contents) and returns the length of the destination string.
 267  * The source and destination strings must be different buffers.
 268  * @param norm2 UNormalizer2 instance
 269  * @param src source string
 270  * @param length length of the source string, or -1 if NUL-terminated
 271  * @param dest destination string; its contents is replaced with normalized src
 272  * @param capacity number of UChars that can be written to dest
 273  * @param pErrorCode Standard ICU error code. Its input value must
 274  *                   pass the U_SUCCESS() test, or else the function returns
 275  *                   immediately. Check for U_FAILURE() on output or use with
 276  *                   function chaining. (See User Guide for details.)
 277  * @return dest
 278  * @stable ICU 4.4
 279  */
 280 U_STABLE int32_t U_EXPORT2
 281 unorm2_normalize(const UNormalizer2 *norm2,
 282                  const UChar *src, int32_t length,
 283                  UChar *dest, int32_t capacity,
 284                  UErrorCode *pErrorCode);
 285 /**
 286  * Appends the normalized form of the second string to the first string
 287  * (merging them at the boundary) and returns the length of the first string.
 288  * The result is normalized if the first string was normalized.
 289  * The first and second strings must be different buffers.
 290  * @param norm2 UNormalizer2 instance
 291  * @param first string, should be normalized
 292  * @param firstLength length of the first string, or -1 if NUL-terminated
 293  * @param firstCapacity number of UChars that can be written to first
 294  * @param second string, will be normalized
 295  * @param secondLength length of the source string, or -1 if NUL-terminated
 296  * @param pErrorCode Standard ICU error code. Its input value must
 297  *                   pass the U_SUCCESS() test, or else the function returns
 298  *                   immediately. Check for U_FAILURE() on output or use with
 299  *                   function chaining. (See User Guide for details.)
 300  * @return first
 301  * @stable ICU 4.4
 302  */
 303 U_STABLE int32_t U_EXPORT2
 304 unorm2_normalizeSecondAndAppend(const UNormalizer2 *norm2,
 305                                 UChar *first, int32_t firstLength, int32_t firstCapacity,
 306                                 const UChar *second, int32_t secondLength,
 307                                 UErrorCode *pErrorCode);
 308 /**
 309  * Appends the second string to the first string
 310  * (merging them at the boundary) and returns the length of the first string.
 311  * The result is normalized if both the strings were normalized.
 312  * The first and second strings must be different buffers.
 313  * @param norm2 UNormalizer2 instance
 314  * @param first string, should be normalized
 315  * @param firstLength length of the first string, or -1 if NUL-terminated
 316  * @param firstCapacity number of UChars that can be written to first
 317  * @param second string, should be normalized
 318  * @param secondLength length of the source string, or -1 if NUL-terminated
 319  * @param pErrorCode Standard ICU error code. Its input value must
 320  *                   pass the U_SUCCESS() test, or else the function returns
 321  *                   immediately. Check for U_FAILURE() on output or use with
 322  *                   function chaining. (See User Guide for details.)
 323  * @return first
 324  * @stable ICU 4.4
 325  */
 326 U_STABLE int32_t U_EXPORT2
 327 unorm2_append(const UNormalizer2 *norm2,
 328               UChar *first, int32_t firstLength, int32_t firstCapacity,
 329               const UChar *second, int32_t secondLength,
 330               UErrorCode *pErrorCode);
 331
 332 /**
 333  * Gets the decomposition mapping of c.
 334  * Roughly equivalent to normalizing the String form of c
 335  * on a UNORM2_DECOMPOSE UNormalizer2 instance, but much faster, and except that this function
 336  * returns a negative value and does not write a string
 337  * if c does not have a decomposition mapping in this instance's data.
 338  * This function is independent of the mode of the UNormalizer2.
 339  * @param norm2 UNormalizer2 instance
 340  * @param c code point
 341  * @param decomposition String buffer which will be set to c's
 342  *                      decomposition mapping, if there is one.
 343  * @param capacity number of UChars that can be written to decomposition
 344  * @param pErrorCode Standard ICU error code. Its input value must
 345  *                   pass the U_SUCCESS() test, or else the function returns
 346  *                   immediately. Check for U_FAILURE() on output or use with
 347  *                   function chaining. (See User Guide for details.)
 348  * @return the non-negative length of c's decomposition, if there is one; otherwise a negative value
 349  * @stable ICU 4.6
 350  */
 351 U_STABLE int32_t U_EXPORT2
 352 unorm2_getDecomposition(const UNormalizer2 *norm2,
 353                         UChar32 c, UChar *decomposition, int32_t capacity,
 354                         UErrorCode *pErrorCode);
 355
 356 /**
 357  * Gets the raw decomposition mapping of c.
 358  *
 359  * This is similar to the unorm2_getDecomposition() function but returns the
 360  * raw decomposition mapping as specified in UnicodeData.txt or
 361  * (for custom data) in the mapping files processed by the gennorm2 tool.
 362  * By contrast, unorm2_getDecomposition() returns the processed,
 363  * recursively-decomposed version of this mapping.
 364  *
 365  * When used on a standard NFKC Normalizer2 instance,
 366  * unorm2_getRawDecomposition() returns the Unicode Decomposition_Mapping (dm) property.
 367  *
 368  * When used on a standard NFC Normalizer2 instance,
 369  * it returns the Decomposition_Mapping only if the Decomposition_Type (dt) is Canonical (Can);
 370  * in this case, the result contains either one or two code points (=1..4 UChars).
 371  *
 372  * This function is independent of the mode of the UNormalizer2.
 373  * @param norm2 UNormalizer2 instance
 374  * @param c code point
 375  * @param decomposition String buffer which will be set to c's
 376  *                      raw decomposition mapping, if there is one.
 377  * @param capacity number of UChars that can be written to decomposition
 378  * @param pErrorCode Standard ICU error code. Its input value must
 379  *                   pass the U_SUCCESS() test, or else the function returns
 380  *                   immediately. Check for U_FAILURE() on output or use with
 381  *                   function chaining. (See User Guide for details.)
 382  * @return the non-negative length of c's raw decomposition, if there is one; otherwise a negative value
 383  * @stable ICU 49
 384  */
 385 U_STABLE int32_t U_EXPORT2
 386 unorm2_getRawDecomposition(const UNormalizer2 *norm2,
 387                            UChar32 c, UChar *decomposition, int32_t capacity,
 388                            UErrorCode *pErrorCode);
 389
 390 /**
 391  * Performs pairwise composition of a & b and returns the composite if there is one.
 392  *
 393  * Returns a composite code point c only if c has a two-way mapping to a+b.
 394  * In standard Unicode normalization, this means that
 395  * c has a canonical decomposition to a+b
 396  * and c does not have the Full_Composition_Exclusion property.
 397  *
 398  * This function is independent of the mode of the UNormalizer2.
 399  * @param norm2 UNormalizer2 instance
 400  * @param a A (normalization starter) code point.
 401  * @param b Another code point.
 402  * @return The non-negative composite code point if there is one; otherwise a negative value.
 403  * @stable ICU 49
 404  */
 405 U_STABLE UChar32 U_EXPORT2
 406 unorm2_composePair(const UNormalizer2 *norm2, UChar32 a, UChar32 b);
 407
 408 /**
 409  * Gets the combining class of c.
 410  * The default implementation returns 0
 411  * but all standard implementations return the Unicode Canonical_Combining_Class value.
 412  * @param norm2 UNormalizer2 instance
 413  * @param c code point
 414  * @return c's combining class
 415  * @stable ICU 49
 416  */
 417 U_STABLE uint8_t U_EXPORT2
 418 unorm2_getCombiningClass(const UNormalizer2 *norm2, UChar32 c);
 419
 420 /**
 421  * Tests if the string is normalized.
 422  * Internally, in cases where the quickCheck() method would return "maybe"
 423  * (which is only possible for the two COMPOSE modes) this method
 424  * resolves to "yes" or "no" to provide a definitive result,
 425  * at the cost of doing more work in those cases.
 426  * @param norm2 UNormalizer2 instance
 427  * @param s input string
 428  * @param length length of the string, or -1 if NUL-terminated
 429  * @param pErrorCode Standard ICU error code. Its input value must
 430  *                   pass the U_SUCCESS() test, or else the function returns
 431  *                   immediately. Check for U_FAILURE() on output or use with
 432  *                   function chaining. (See User Guide for details.)
 433  * @return TRUE if s is normalized
 434  * @stable ICU 4.4
 435  */
 436 U_STABLE UBool U_EXPORT2
 437 unorm2_isNormalized(const UNormalizer2 *norm2,
 438                     const UChar *s, int32_t length,
 439                     UErrorCode *pErrorCode);
 440
 441 /**
 442  * Tests if the string is normalized.
 443  * For the two COMPOSE modes, the result could be "maybe" in cases that
 444  * would take a little more work to resolve definitively.
 445  * Use spanQuickCheckYes() and normalizeSecondAndAppend() for a faster
 446  * combination of quick check + normalization, to avoid
 447  * re-checking the "yes" prefix.
 448  * @param norm2 UNormalizer2 instance
 449  * @param s input string
 450  * @param length length of the string, or -1 if NUL-terminated
 451  * @param pErrorCode Standard ICU error code. Its input value must
 452  *                   pass the U_SUCCESS() test, or else the function returns
 453  *                   immediately. Check for U_FAILURE() on output or use with
 454  *                   function chaining. (See User Guide for details.)
 455  * @return UNormalizationCheckResult
 456  * @stable ICU 4.4
 457  */
 458 U_STABLE UNormalizationCheckResult U_EXPORT2
 459 unorm2_quickCheck(const UNormalizer2 *norm2,
 460                   const UChar *s, int32_t length,
 461                   UErrorCode *pErrorCode);
 462
 463 /**
 464  * Returns the end of the normalized substring of the input string.
 465  * In other words, with <code>end=spanQuickCheckYes(s, ec);</code>
 466  * the substring <code>UnicodeString(s, 0, end)</code>
 467  * will pass the quick check with a "yes" result.
 468  *
 469  * The returned end index is usually one or more characters before the
 470  * "no" or "maybe" character: The end index is at a normalization boundary.
 471  * (See the class documentation for more about normalization boundaries.)
 472  *
 473  * When the goal is a normalized string and most input strings are expected
 474  * to be normalized already, then call this method,
 475  * and if it returns a prefix shorter than the input string,
 476  * copy that prefix and use normalizeSecondAndAppend() for the remainder.
 477  * @param norm2 UNormalizer2 instance
 478  * @param s input string
 479  * @param length length of the string, or -1 if NUL-terminated
 480  * @param pErrorCode Standard ICU error code. Its input value must
 481  *                   pass the U_SUCCESS() test, or else the function returns
 482  *                   immediately. Check for U_FAILURE() on output or use with
 483  *                   function chaining. (See User Guide for details.)
 484  * @return "yes" span end index
 485  * @stable ICU 4.4
 486  */
 487 U_STABLE int32_t U_EXPORT2
 488 unorm2_spanQuickCheckYes(const UNormalizer2 *norm2,
 489                          const UChar *s, int32_t length,
 490                          UErrorCode *pErrorCode);
 491
 492 /**
 493  * Tests if the character always has a normalization boundary before it,
 494  * regardless of context.
 495  * For details see the Normalizer2 base class documentation.
 496  * @param norm2 UNormalizer2 instance
 497  * @param c character to test
 498  * @return TRUE if c has a normalization boundary before it
 499  * @stable ICU 4.4
 500  */
 501 U_STABLE UBool U_EXPORT2
 502 unorm2_hasBoundaryBefore(const UNormalizer2 *norm2, UChar32 c);
 503
 504 /**
 505  * Tests if the character always has a normalization boundary after it,
 506  * regardless of context.
 507  * For details see the Normalizer2 base class documentation.
 508  * @param norm2 UNormalizer2 instance
 509  * @param c character to test
 510  * @return TRUE if c has a normalization boundary after it
 511  * @stable ICU 4.4
 512  */
 513 U_STABLE UBool U_EXPORT2
 514 unorm2_hasBoundaryAfter(const UNormalizer2 *norm2, UChar32 c);
 515
 516 /**
 517  * Tests if the character is normalization-inert.
 518  * For details see the Normalizer2 base class documentation.
 519  * @param norm2 UNormalizer2 instance
 520  * @param c character to test
 521  * @return TRUE if c is normalization-inert
 522  * @stable ICU 4.4
 523  */
 524 U_STABLE UBool U_EXPORT2
 525 unorm2_isInert(const UNormalizer2 *norm2, UChar32 c);
 526
 527 /**
 528  * Option bit for unorm_compare:
 529  * Both input strings are assumed to fulfill FCD conditions.
 530  * @stable ICU 2.2
 531  */
 532 #define UNORM_INPUT_IS_FCD          0x20000
 533
 534 /**
 535  * Option bit for unorm_compare:
 536  * Perform case-insensitive comparison.
 537  * @stable ICU 2.2
 538  */
 539 #define U_COMPARE_IGNORE_CASE       0x10000
 540
 541 #ifndef U_COMPARE_CODE_POINT_ORDER
 542 /* see also unistr.h and ustring.h */
 543 /**
 544  * Option bit for u_strCaseCompare, u_strcasecmp, unorm_compare, etc:
 545  * Compare strings in code point order instead of code unit order.
 546  * @stable ICU 2.2
 547  */
 548 #define U_COMPARE_CODE_POINT_ORDER  0x8000
 549 #endif
 550
 551 /**
 552  * Compares two strings for canonical equivalence.
 553  * Further options include case-insensitive comparison and
 554  * code point order (as opposed to code unit order).
 555  *
 556  * Canonical equivalence between two strings is defined as their normalized
 557  * forms (NFD or NFC) being identical.
 558  * This function compares strings incrementally instead of normalizing
 559  * (and optionally case-folding) both strings entirely,
 560  * improving performance significantly.
 561  *
 562  * Bulk normalization is only necessary if the strings do not fulfill the FCD
 563  * conditions. Only in this case, and only if the strings are relatively long,
 564  * is memory allocated temporarily.
 565  * For FCD strings and short non-FCD strings there is no memory allocation.
 566  *
 567  * Semantically, this is equivalent to
 568  *   strcmp[CodePointOrder](NFD(foldCase(NFD(s1))), NFD(foldCase(NFD(s2))))
 569  * where code point order and foldCase are all optional.
 570  *
 571  * UAX 21 2.5 Caseless Matching specifies that for a canonical caseless match
 572  * the case folding must be performed first, then the normalization.
 573  *
 574  * @param s1 First source string.
 575  * @param length1 Length of first source string, or -1 if NUL-terminated.
 576  *
 577  * @param s2 Second source string.
 578  * @param length2 Length of second source string, or -1 if NUL-terminated.
 579  *
 580  * @param options A bit set of options:
 581  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
 582  *     Case-sensitive comparison in code unit order, and the input strings
 583  *     are quick-checked for FCD.
 584  *
 585  *   - UNORM_INPUT_IS_FCD
 586  *     Set if the caller knows that both s1 and s2 fulfill the FCD conditions.
 587  *     If not set, the function will quickCheck for FCD
 588  *     and normalize if necessary.
 589  *
 590  *   - U_COMPARE_CODE_POINT_ORDER
 591  *     Set to choose code point order instead of code unit order
 592  *     (see u_strCompare for details).
 593  *
 594  *   - U_COMPARE_IGNORE_CASE
 595  *     Set to compare strings case-insensitively using case folding,
 596  *     instead of case-sensitively.
 597  *     If set, then the following case folding options are used.
 598  *
 599  *   - Options as used with case-insensitive comparisons, currently:
 600  *
 601  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
 602  *    (see u_strCaseCompare for details)
 603  *
 604  *   - regular normalization options shifted left by UNORM_COMPARE_NORM_OPTIONS_SHIFT
 605  *
 606  * @param pErrorCode ICU error code in/out parameter.
 607  *                   Must fulfill U_SUCCESS before the function call.
 608  * @return <0 or 0 or >0 as usual for string comparisons
 609  *
 610  * @see unorm_normalize
 611  * @see UNORM_FCD
 612  * @see u_strCompare
 613  * @see u_strCaseCompare
 614  *
 615  * @stable ICU 2.2
 616  */
 617 U_STABLE int32_t U_EXPORT2
 618 unorm_compare(const UChar *s1, int32_t length1,
 619               const UChar *s2, int32_t length2,
 620               uint32_t options,
 621               UErrorCode *pErrorCode);
 622
 623 #endif  /* !UCONFIG_NO_NORMALIZATION */
 624 #endif  /* __UNORM2_H__ */