summaryrefslogtreecommitdiffstats
path: root/intl/icu/source/common/unicode/unorm2.h
blob: 56e99b2a22b4137913056f4ba32431b9ebe53b8e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
// Copyright (C) 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
*
*   Copyright (C) 2009-2015, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*   file name:  unorm2.h
*   encoding:   US-ASCII
*   tab size:   8 (not used)
*   indentation:4
*
*   created on: 2009dec15
*   created by: Markus W. Scherer
*/

#ifndef __UNORM2_H__
#define __UNORM2_H__

/**
 * \file
 * \brief C API: New API for Unicode Normalization.
 *
 * Unicode normalization functionality for standard Unicode normalization or
 * for using custom mapping tables.
 * All instances of UNormalizer2 are unmodifiable/immutable.
 * Instances returned by unorm2_getInstance() are singletons that must not be deleted by the caller.
 * For more details see the Normalizer2 C++ class.
 */

#include "unicode/utypes.h"
#include "unicode/localpointer.h"
#include "unicode/uset.h"

/**
 * Constants for normalization modes.
 * For details about standard Unicode normalization forms
 * and about the algorithms which are also used with custom mapping tables
 * see http://www.unicode.org/unicode/reports/tr15/
 * @stable ICU 4.4
 */
typedef enum {
    /**
     * Decomposition followed by composition.
     * Same as standard NFC when using an "nfc" instance.
     * Same as standard NFKC when using an "nfkc" instance.
     * For details about standard Unicode normalization forms
     * see http://www.unicode.org/unicode/reports/tr15/
     * @stable ICU 4.4
     */
    UNORM2_COMPOSE,
    /**
     * Map, and reorder canonically.
     * Same as standard NFD when using an "nfc" instance.
     * Same as standard NFKD when using an "nfkc" instance.
     * For details about standard Unicode normalization forms
     * see http://www.unicode.org/unicode/reports/tr15/
     * @stable ICU 4.4
     */
    UNORM2_DECOMPOSE,
    /**
     * "Fast C or D" form.
     * If a string is in this form, then further decomposition <i>without reordering</i>
     * would yield the same form as DECOMPOSE.
     * Text in "Fast C or D" form can be processed efficiently with data tables
     * that are "canonically closed", that is, that provide equivalent data for
     * equivalent text, without having to be fully normalized.
     * Not a standard Unicode normalization form.
     * Not a unique form: Different FCD strings can be canonically equivalent.
     * For details see http://www.unicode.org/notes/tn5/#FCD
     * @stable ICU 4.4
     */
    UNORM2_FCD,
    /**
     * Compose only contiguously.
     * Also known as "FCC" or "Fast C Contiguous".
     * The result will often but not always be in NFC.
     * The result will conform to FCD which is useful for processing.
     * Not a standard Unicode normalization form.
     * For details see http://www.unicode.org/notes/tn5/#FCC
     * @stable ICU 4.4
     */
    UNORM2_COMPOSE_CONTIGUOUS
} UNormalization2Mode;

/**
 * Result values for normalization quick check functions.
 * For details see http://www.unicode.org/reports/tr15/#Detecting_Normalization_Forms
 * @stable ICU 2.0
 */
typedef enum UNormalizationCheckResult {
  /**
   * The input string is not in the normalization form.
   * @stable ICU 2.0
   */
  UNORM_NO,
  /**
   * The input string is in the normalization form.
   * @stable ICU 2.0
   */
  UNORM_YES,
  /**
   * The input string may or may not be in the normalization form.
   * This value is only returned for composition forms like NFC and FCC,
   * when a backward-combining character is found for which the surrounding text
   * would have to be analyzed further.
   * @stable ICU 2.0
   */
  UNORM_MAYBE
} UNormalizationCheckResult;

/**
 * Opaque C service object type for the new normalization API.
 * @stable ICU 4.4
 */
struct UNormalizer2;
typedef struct UNormalizer2 UNormalizer2;  /**< C typedef for struct UNormalizer2. @stable ICU 4.4 */

#if !UCONFIG_NO_NORMALIZATION

/**
 * Returns a UNormalizer2 instance for Unicode NFC normalization.
 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_COMPOSE, pErrorCode).
 * Returns an unmodifiable singleton instance. Do not delete it.
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested Normalizer2, if successful
 * @stable ICU 49
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getNFCInstance(UErrorCode *pErrorCode);

/**
 * Returns a UNormalizer2 instance for Unicode NFD normalization.
 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_DECOMPOSE, pErrorCode).
 * Returns an unmodifiable singleton instance. Do not delete it.
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested Normalizer2, if successful
 * @stable ICU 49
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getNFDInstance(UErrorCode *pErrorCode);

/**
 * Returns a UNormalizer2 instance for Unicode NFKC normalization.
 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_COMPOSE, pErrorCode).
 * Returns an unmodifiable singleton instance. Do not delete it.
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested Normalizer2, if successful
 * @stable ICU 49
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getNFKCInstance(UErrorCode *pErrorCode);

/**
 * Returns a UNormalizer2 instance for Unicode NFKD normalization.
 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_DECOMPOSE, pErrorCode).
 * Returns an unmodifiable singleton instance. Do not delete it.
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested Normalizer2, if successful
 * @stable ICU 49
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getNFKDInstance(UErrorCode *pErrorCode);

/**
 * Returns a UNormalizer2 instance for Unicode NFKC_Casefold normalization.
 * Same as unorm2_getInstance(NULL, "nfkc_cf", UNORM2_COMPOSE, pErrorCode).
 * Returns an unmodifiable singleton instance. Do not delete it.
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested Normalizer2, if successful
 * @stable ICU 49
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getNFKCCasefoldInstance(UErrorCode *pErrorCode);

/**
 * Returns a UNormalizer2 instance which uses the specified data file
 * (packageName/name similar to ucnv_openPackage() and ures_open()/ResourceBundle)
 * and which composes or decomposes text according to the specified mode.
 * Returns an unmodifiable singleton instance. Do not delete it.
 *
 * Use packageName=NULL for data files that are part of ICU's own data.
 * Use name="nfc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFC/NFD.
 * Use name="nfkc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFKC/NFKD.
 * Use name="nfkc_cf" and UNORM2_COMPOSE for Unicode standard NFKC_CF=NFKC_Casefold.
 *
 * @param packageName NULL for ICU built-in data, otherwise application data package name
 * @param name "nfc" or "nfkc" or "nfkc_cf" or name of custom data file
 * @param mode normalization mode (compose or decompose etc.)
 * @param pErrorCode Standard ICU error code. Its input value must
 *                  pass the U_SUCCESS() test, or else the function returns
 *                  immediately. Check for U_FAILURE() on output or use with
 *                  function chaining. (See User Guide for details.)
 * @return the requested UNormalizer2, if successful
 * @stable ICU 4.4
 */
U_STABLE const UNormalizer2 * U_EXPORT2
unorm2_getInstance(const char *packageName,
                   const char *name,
                   UNormalization2Mode mode,
                   UErrorCode *pErrorCode);

/**
 * Constructs a filtered normalizer wrapping any UNormalizer2 instance
 * and a filter set.
 * Both are aliased and must not be modified or deleted while this object
 * is used.
 * The filter set should be frozen; otherwise the performance will suffer greatly.
 * @param norm2 wrapped UNormalizer2 instance
 * @param filterSet USet which determines the characters to be normalized
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return the requested UNormalizer2, if successful
 * @stable ICU 4.4
 */
U_STABLE UNormalizer2 * U_EXPORT2
unorm2_openFiltered(const UNormalizer2 *norm2, const USet *filterSet, UErrorCode *pErrorCode);

/**
 * Closes a UNormalizer2 instance from unorm2_openFiltered().
 * Do not close instances from unorm2_getInstance()!
 * @param norm2 UNormalizer2 instance to be closed
 * @stable ICU 4.4
 */
U_STABLE void U_EXPORT2
unorm2_close(UNormalizer2 *norm2);

#if U_SHOW_CPLUSPLUS_API

U_NAMESPACE_BEGIN

/**
 * \class LocalUNormalizer2Pointer
 * "Smart pointer" class, closes a UNormalizer2 via unorm2_close().
 * For most methods see the LocalPointerBase base class.
 *
 * @see LocalPointerBase
 * @see LocalPointer
 * @stable ICU 4.4
 */
U_DEFINE_LOCAL_OPEN_POINTER(LocalUNormalizer2Pointer, UNormalizer2, unorm2_close);

U_NAMESPACE_END

#endif

/**
 * Writes the normalized form of the source string to the destination string
 * (replacing its contents) and returns the length of the destination string.
 * The source and destination strings must be different buffers.
 * @param norm2 UNormalizer2 instance
 * @param src source string
 * @param length length of the source string, or -1 if NUL-terminated
 * @param dest destination string; its contents is replaced with normalized src
 * @param capacity number of UChars that can be written to dest
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return dest
 * @stable ICU 4.4
 */
U_STABLE int32_t U_EXPORT2
unorm2_normalize(const UNormalizer2 *norm2,
                 const UChar *src, int32_t length,
                 UChar *dest, int32_t capacity,
                 UErrorCode *pErrorCode);
/**
 * Appends the normalized form of the second string to the first string
 * (merging them at the boundary) and returns the length of the first string.
 * The result is normalized if the first string was normalized.
 * The first and second strings must be different buffers.
 * @param norm2 UNormalizer2 instance
 * @param first string, should be normalized
 * @param firstLength length of the first string, or -1 if NUL-terminated
 * @param firstCapacity number of UChars that can be written to first
 * @param second string, will be normalized
 * @param secondLength length of the source string, or -1 if NUL-terminated
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return first
 * @stable ICU 4.4
 */
U_STABLE int32_t U_EXPORT2
unorm2_normalizeSecondAndAppend(const UNormalizer2 *norm2,
                                UChar *first, int32_t firstLength, int32_t firstCapacity,
                                const UChar *second, int32_t secondLength,
                                UErrorCode *pErrorCode);
/**
 * Appends the second string to the first string
 * (merging them at the boundary) and returns the length of the first string.
 * The result is normalized if both the strings were normalized.
 * The first and second strings must be different buffers.
 * @param norm2 UNormalizer2 instance
 * @param first string, should be normalized
 * @param firstLength length of the first string, or -1 if NUL-terminated
 * @param firstCapacity number of UChars that can be written to first
 * @param second string, should be normalized
 * @param secondLength length of the source string, or -1 if NUL-terminated
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return first
 * @stable ICU 4.4
 */
U_STABLE int32_t U_EXPORT2
unorm2_append(const UNormalizer2 *norm2,
              UChar *first, int32_t firstLength, int32_t firstCapacity,
              const UChar *second, int32_t secondLength,
              UErrorCode *pErrorCode);

/**
 * Gets the decomposition mapping of c.
 * Roughly equivalent to normalizing the String form of c
 * on a UNORM2_DECOMPOSE UNormalizer2 instance, but much faster, and except that this function
 * returns a negative value and does not write a string
 * if c does not have a decomposition mapping in this instance's data.
 * This function is independent of the mode of the UNormalizer2.
 * @param norm2 UNormalizer2 instance
 * @param c code point
 * @param decomposition String buffer which will be set to c's
 *                      decomposition mapping, if there is one.
 * @param capacity number of UChars that can be written to decomposition
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return the non-negative length of c's decomposition, if there is one; otherwise a negative value
 * @stable ICU 4.6
 */
U_STABLE int32_t U_EXPORT2
unorm2_getDecomposition(const UNormalizer2 *norm2,
                        UChar32 c, UChar *decomposition, int32_t capacity,
                        UErrorCode *pErrorCode);

/**
 * Gets the raw decomposition mapping of c.
 *
 * This is similar to the unorm2_getDecomposition() function but returns the
 * raw decomposition mapping as specified in UnicodeData.txt or
 * (for custom data) in the mapping files processed by the gennorm2 tool.
 * By contrast, unorm2_getDecomposition() returns the processed,
 * recursively-decomposed version of this mapping.
 *
 * When used on a standard NFKC Normalizer2 instance,
 * unorm2_getRawDecomposition() returns the Unicode Decomposition_Mapping (dm) property.
 *
 * When used on a standard NFC Normalizer2 instance,
 * it returns the Decomposition_Mapping only if the Decomposition_Type (dt) is Canonical (Can);
 * in this case, the result contains either one or two code points (=1..4 UChars).
 *
 * This function is independent of the mode of the UNormalizer2.
 * @param norm2 UNormalizer2 instance
 * @param c code point
 * @param decomposition String buffer which will be set to c's
 *                      raw decomposition mapping, if there is one.
 * @param capacity number of UChars that can be written to decomposition
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return the non-negative length of c's raw decomposition, if there is one; otherwise a negative value
 * @stable ICU 49
 */
U_STABLE int32_t U_EXPORT2
unorm2_getRawDecomposition(const UNormalizer2 *norm2,
                           UChar32 c, UChar *decomposition, int32_t capacity,
                           UErrorCode *pErrorCode);

/**
 * Performs pairwise composition of a & b and returns the composite if there is one.
 *
 * Returns a composite code point c only if c has a two-way mapping to a+b.
 * In standard Unicode normalization, this means that
 * c has a canonical decomposition to a+b
 * and c does not have the Full_Composition_Exclusion property.
 *
 * This function is independent of the mode of the UNormalizer2.
 * @param norm2 UNormalizer2 instance
 * @param a A (normalization starter) code point.
 * @param b Another code point.
 * @return The non-negative composite code point if there is one; otherwise a negative value.
 * @stable ICU 49
 */
U_STABLE UChar32 U_EXPORT2
unorm2_composePair(const UNormalizer2 *norm2, UChar32 a, UChar32 b);

/**
 * Gets the combining class of c.
 * The default implementation returns 0
 * but all standard implementations return the Unicode Canonical_Combining_Class value.
 * @param norm2 UNormalizer2 instance
 * @param c code point
 * @return c's combining class
 * @stable ICU 49
 */
U_STABLE uint8_t U_EXPORT2
unorm2_getCombiningClass(const UNormalizer2 *norm2, UChar32 c);

/**
 * Tests if the string is normalized.
 * Internally, in cases where the quickCheck() method would return "maybe"
 * (which is only possible for the two COMPOSE modes) this method
 * resolves to "yes" or "no" to provide a definitive result,
 * at the cost of doing more work in those cases.
 * @param norm2 UNormalizer2 instance
 * @param s input string
 * @param length length of the string, or -1 if NUL-terminated
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return TRUE if s is normalized
 * @stable ICU 4.4
 */
U_STABLE UBool U_EXPORT2
unorm2_isNormalized(const UNormalizer2 *norm2,
                    const UChar *s, int32_t length,
                    UErrorCode *pErrorCode);

/**
 * Tests if the string is normalized.
 * For the two COMPOSE modes, the result could be "maybe" in cases that
 * would take a little more work to resolve definitively.
 * Use spanQuickCheckYes() and normalizeSecondAndAppend() for a faster
 * combination of quick check + normalization, to avoid
 * re-checking the "yes" prefix.
 * @param norm2 UNormalizer2 instance
 * @param s input string
 * @param length length of the string, or -1 if NUL-terminated
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return UNormalizationCheckResult
 * @stable ICU 4.4
 */
U_STABLE UNormalizationCheckResult U_EXPORT2
unorm2_quickCheck(const UNormalizer2 *norm2,
                  const UChar *s, int32_t length,
                  UErrorCode *pErrorCode);

/**
 * Returns the end of the normalized substring of the input string.
 * In other words, with <code>end=spanQuickCheckYes(s, ec);</code>
 * the substring <code>UnicodeString(s, 0, end)</code>
 * will pass the quick check with a "yes" result.
 *
 * The returned end index is usually one or more characters before the
 * "no" or "maybe" character: The end index is at a normalization boundary.
 * (See the class documentation for more about normalization boundaries.)
 *
 * When the goal is a normalized string and most input strings are expected
 * to be normalized already, then call this method,
 * and if it returns a prefix shorter than the input string,
 * copy that prefix and use normalizeSecondAndAppend() for the remainder.
 * @param norm2 UNormalizer2 instance
 * @param s input string
 * @param length length of the string, or -1 if NUL-terminated
 * @param pErrorCode Standard ICU error code. Its input value must
 *                   pass the U_SUCCESS() test, or else the function returns
 *                   immediately. Check for U_FAILURE() on output or use with
 *                   function chaining. (See User Guide for details.)
 * @return "yes" span end index
 * @stable ICU 4.4
 */
U_STABLE int32_t U_EXPORT2
unorm2_spanQuickCheckYes(const UNormalizer2 *norm2,
                         const UChar *s, int32_t length,
                         UErrorCode *pErrorCode);

/**
 * Tests if the character always has a normalization boundary before it,
 * regardless of context.
 * For details see the Normalizer2 base class documentation.
 * @param norm2 UNormalizer2 instance
 * @param c character to test
 * @return TRUE if c has a normalization boundary before it
 * @stable ICU 4.4
 */
U_STABLE UBool U_EXPORT2
unorm2_hasBoundaryBefore(const UNormalizer2 *norm2, UChar32 c);

/**
 * Tests if the character always has a normalization boundary after it,
 * regardless of context.
 * For details see the Normalizer2 base class documentation.
 * @param norm2 UNormalizer2 instance
 * @param c character to test
 * @return TRUE if c has a normalization boundary after it
 * @stable ICU 4.4
 */
U_STABLE UBool U_EXPORT2
unorm2_hasBoundaryAfter(const UNormalizer2 *norm2, UChar32 c);

/**
 * Tests if the character is normalization-inert.
 * For details see the Normalizer2 base class documentation.
 * @param norm2 UNormalizer2 instance
 * @param c character to test
 * @return TRUE if c is normalization-inert
 * @stable ICU 4.4
 */
U_STABLE UBool U_EXPORT2
unorm2_isInert(const UNormalizer2 *norm2, UChar32 c);

/**
 * Option bit for unorm_compare:
 * Both input strings are assumed to fulfill FCD conditions.
 * @stable ICU 2.2
 */
#define UNORM_INPUT_IS_FCD          0x20000

/**
 * Option bit for unorm_compare:
 * Perform case-insensitive comparison.
 * @stable ICU 2.2
 */
#define U_COMPARE_IGNORE_CASE       0x10000

#ifndef U_COMPARE_CODE_POINT_ORDER
/* see also unistr.h and ustring.h */
/**
 * Option bit for u_strCaseCompare, u_strcasecmp, unorm_compare, etc:
 * Compare strings in code point order instead of code unit order.
 * @stable ICU 2.2
 */
#define U_COMPARE_CODE_POINT_ORDER  0x8000
#endif

/**
 * Compares two strings for canonical equivalence.
 * Further options include case-insensitive comparison and
 * code point order (as opposed to code unit order).
 *
 * Canonical equivalence between two strings is defined as their normalized
 * forms (NFD or NFC) being identical.
 * This function compares strings incrementally instead of normalizing
 * (and optionally case-folding) both strings entirely,
 * improving performance significantly.
 *
 * Bulk normalization is only necessary if the strings do not fulfill the FCD
 * conditions. Only in this case, and only if the strings are relatively long,
 * is memory allocated temporarily.
 * For FCD strings and short non-FCD strings there is no memory allocation.
 *
 * Semantically, this is equivalent to
 *   strcmp[CodePointOrder](NFD(foldCase(NFD(s1))), NFD(foldCase(NFD(s2))))
 * where code point order and foldCase are all optional.
 *
 * UAX 21 2.5 Caseless Matching specifies that for a canonical caseless match
 * the case folding must be performed first, then the normalization.
 *
 * @param s1 First source string.
 * @param length1 Length of first source string, or -1 if NUL-terminated.
 *
 * @param s2 Second source string.
 * @param length2 Length of second source string, or -1 if NUL-terminated.
 *
 * @param options A bit set of options:
 *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
 *     Case-sensitive comparison in code unit order, and the input strings
 *     are quick-checked for FCD.
 *
 *   - UNORM_INPUT_IS_FCD
 *     Set if the caller knows that both s1 and s2 fulfill the FCD conditions.
 *     If not set, the function will quickCheck for FCD
 *     and normalize if necessary.
 *
 *   - U_COMPARE_CODE_POINT_ORDER
 *     Set to choose code point order instead of code unit order
 *     (see u_strCompare for details).
 *
 *   - U_COMPARE_IGNORE_CASE
 *     Set to compare strings case-insensitively using case folding,
 *     instead of case-sensitively.
 *     If set, then the following case folding options are used.
 *
 *   - Options as used with case-insensitive comparisons, currently:
 *
 *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
 *    (see u_strCaseCompare for details)
 *
 *   - regular normalization options shifted left by UNORM_COMPARE_NORM_OPTIONS_SHIFT
 *
 * @param pErrorCode ICU error code in/out parameter.
 *                   Must fulfill U_SUCCESS before the function call.
 * @return <0 or 0 or >0 as usual for string comparisons
 *
 * @see unorm_normalize
 * @see UNORM_FCD
 * @see u_strCompare
 * @see u_strCaseCompare
 *
 * @stable ICU 2.2
 */
U_STABLE int32_t U_EXPORT2
unorm_compare(const UChar *s1, int32_t length1,
              const UChar *s2, int32_t length2,
              uint32_t options,
              UErrorCode *pErrorCode);

#endif  /* !UCONFIG_NO_NORMALIZATION */
#endif  /* __UNORM2_H__ */