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1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
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3/*
4*******************************************************************************
5*
2ca993e8 6* Copyright (C) 2009-2015, International Business Machines
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7* Corporation and others. All Rights Reserved.
8*
9*******************************************************************************
10* file name: unorm2.h
f3c0d7a5 11* encoding: UTF-8
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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/localpointer.h"
35#include "unicode/uset.h"
36
37/**
38 * Constants for normalization modes.
39 * For details about standard Unicode normalization forms
40 * and about the algorithms which are also used with custom mapping tables
41 * see http://www.unicode.org/unicode/reports/tr15/
42 * @stable ICU 4.4
43 */
44typedef enum {
45 /**
46 * Decomposition followed by composition.
47 * Same as standard NFC when using an "nfc" instance.
48 * Same as standard NFKC when using an "nfkc" instance.
49 * For details about standard Unicode normalization forms
50 * see http://www.unicode.org/unicode/reports/tr15/
51 * @stable ICU 4.4
52 */
53 UNORM2_COMPOSE,
54 /**
55 * Map, and reorder canonically.
56 * Same as standard NFD when using an "nfc" instance.
57 * Same as standard NFKD when using an "nfkc" instance.
58 * For details about standard Unicode normalization forms
59 * see http://www.unicode.org/unicode/reports/tr15/
60 * @stable ICU 4.4
61 */
62 UNORM2_DECOMPOSE,
63 /**
64 * "Fast C or D" form.
65 * If a string is in this form, then further decomposition <i>without reordering</i>
66 * would yield the same form as DECOMPOSE.
67 * Text in "Fast C or D" form can be processed efficiently with data tables
68 * that are "canonically closed", that is, that provide equivalent data for
69 * equivalent text, without having to be fully normalized.
70 * Not a standard Unicode normalization form.
71 * Not a unique form: Different FCD strings can be canonically equivalent.
72 * For details see http://www.unicode.org/notes/tn5/#FCD
73 * @stable ICU 4.4
74 */
75 UNORM2_FCD,
76 /**
77 * Compose only contiguously.
78 * Also known as "FCC" or "Fast C Contiguous".
79 * The result will often but not always be in NFC.
80 * The result will conform to FCD which is useful for processing.
81 * Not a standard Unicode normalization form.
82 * For details see http://www.unicode.org/notes/tn5/#FCC
83 * @stable ICU 4.4
84 */
85 UNORM2_COMPOSE_CONTIGUOUS
86} UNormalization2Mode;
87
88/**
89 * Result values for normalization quick check functions.
90 * For details see http://www.unicode.org/reports/tr15/#Detecting_Normalization_Forms
91 * @stable ICU 2.0
92 */
93typedef enum UNormalizationCheckResult {
94 /**
95 * The input string is not in the normalization form.
96 * @stable ICU 2.0
97 */
98 UNORM_NO,
99 /**
100 * The input string is in the normalization form.
101 * @stable ICU 2.0
102 */
103 UNORM_YES,
104 /**
105 * The input string may or may not be in the normalization form.
106 * This value is only returned for composition forms like NFC and FCC,
107 * when a backward-combining character is found for which the surrounding text
108 * would have to be analyzed further.
109 * @stable ICU 2.0
110 */
111 UNORM_MAYBE
112} UNormalizationCheckResult;
113
114/**
115 * Opaque C service object type for the new normalization API.
116 * @stable ICU 4.4
117 */
118struct UNormalizer2;
119typedef struct UNormalizer2 UNormalizer2; /**< C typedef for struct UNormalizer2. @stable ICU 4.4 */
120
121#if !UCONFIG_NO_NORMALIZATION
122
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123/**
124 * Returns a UNormalizer2 instance for Unicode NFC normalization.
125 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_COMPOSE, pErrorCode).
126 * Returns an unmodifiable singleton instance. Do not delete it.
51004dcb 127 * @param pErrorCode Standard ICU error code. Its input value must
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128 * pass the U_SUCCESS() test, or else the function returns
129 * immediately. Check for U_FAILURE() on output or use with
130 * function chaining. (See User Guide for details.)
131 * @return the requested Normalizer2, if successful
51004dcb 132 * @stable ICU 49
4388f060 133 */
51004dcb 134U_STABLE const UNormalizer2 * U_EXPORT2
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135unorm2_getNFCInstance(UErrorCode *pErrorCode);
136
137/**
138 * Returns a UNormalizer2 instance for Unicode NFD normalization.
139 * Same as unorm2_getInstance(NULL, "nfc", UNORM2_DECOMPOSE, pErrorCode).
140 * Returns an unmodifiable singleton instance. Do not delete it.
51004dcb 141 * @param pErrorCode Standard ICU error code. Its input value must
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142 * pass the U_SUCCESS() test, or else the function returns
143 * immediately. Check for U_FAILURE() on output or use with
144 * function chaining. (See User Guide for details.)
145 * @return the requested Normalizer2, if successful
51004dcb 146 * @stable ICU 49
4388f060 147 */
51004dcb 148U_STABLE const UNormalizer2 * U_EXPORT2
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149unorm2_getNFDInstance(UErrorCode *pErrorCode);
150
151/**
152 * Returns a UNormalizer2 instance for Unicode NFKC normalization.
153 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_COMPOSE, pErrorCode).
154 * Returns an unmodifiable singleton instance. Do not delete it.
51004dcb 155 * @param pErrorCode Standard ICU error code. Its input value must
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156 * pass the U_SUCCESS() test, or else the function returns
157 * immediately. Check for U_FAILURE() on output or use with
158 * function chaining. (See User Guide for details.)
159 * @return the requested Normalizer2, if successful
51004dcb 160 * @stable ICU 49
4388f060 161 */
51004dcb 162U_STABLE const UNormalizer2 * U_EXPORT2
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163unorm2_getNFKCInstance(UErrorCode *pErrorCode);
164
165/**
166 * Returns a UNormalizer2 instance for Unicode NFKD normalization.
167 * Same as unorm2_getInstance(NULL, "nfkc", UNORM2_DECOMPOSE, pErrorCode).
168 * Returns an unmodifiable singleton instance. Do not delete it.
51004dcb 169 * @param pErrorCode Standard ICU error code. Its input value must
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170 * pass the U_SUCCESS() test, or else the function returns
171 * immediately. Check for U_FAILURE() on output or use with
172 * function chaining. (See User Guide for details.)
173 * @return the requested Normalizer2, if successful
51004dcb 174 * @stable ICU 49
4388f060 175 */
51004dcb 176U_STABLE const UNormalizer2 * U_EXPORT2
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177unorm2_getNFKDInstance(UErrorCode *pErrorCode);
178
179/**
180 * Returns a UNormalizer2 instance for Unicode NFKC_Casefold normalization.
181 * Same as unorm2_getInstance(NULL, "nfkc_cf", UNORM2_COMPOSE, pErrorCode).
182 * Returns an unmodifiable singleton instance. Do not delete it.
51004dcb 183 * @param pErrorCode Standard ICU error code. Its input value must
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184 * pass the U_SUCCESS() test, or else the function returns
185 * immediately. Check for U_FAILURE() on output or use with
186 * function chaining. (See User Guide for details.)
187 * @return the requested Normalizer2, if successful
51004dcb 188 * @stable ICU 49
4388f060 189 */
51004dcb 190U_STABLE const UNormalizer2 * U_EXPORT2
4388f060 191unorm2_getNFKCCasefoldInstance(UErrorCode *pErrorCode);
4388f060 192
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193/**
194 * Returns a UNormalizer2 instance which uses the specified data file
195 * (packageName/name similar to ucnv_openPackage() and ures_open()/ResourceBundle)
196 * and which composes or decomposes text according to the specified mode.
197 * Returns an unmodifiable singleton instance. Do not delete it.
198 *
199 * Use packageName=NULL for data files that are part of ICU's own data.
200 * Use name="nfc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFC/NFD.
201 * Use name="nfkc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFKC/NFKD.
202 * Use name="nfkc_cf" and UNORM2_COMPOSE for Unicode standard NFKC_CF=NFKC_Casefold.
203 *
204 * @param packageName NULL for ICU built-in data, otherwise application data package name
205 * @param name "nfc" or "nfkc" or "nfkc_cf" or name of custom data file
206 * @param mode normalization mode (compose or decompose etc.)
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 UNormalizer2, if successful
212 * @stable ICU 4.4
213 */
214U_STABLE const UNormalizer2 * U_EXPORT2
215unorm2_getInstance(const char *packageName,
216 const char *name,
217 UNormalization2Mode mode,
218 UErrorCode *pErrorCode);
219
220/**
221 * Constructs a filtered normalizer wrapping any UNormalizer2 instance
222 * and a filter set.
223 * Both are aliased and must not be modified or deleted while this object
224 * is used.
225 * The filter set should be frozen; otherwise the performance will suffer greatly.
226 * @param norm2 wrapped UNormalizer2 instance
227 * @param filterSet USet which determines the characters to be normalized
228 * @param pErrorCode Standard ICU error code. Its input value must
229 * pass the U_SUCCESS() test, or else the function returns
230 * immediately. Check for U_FAILURE() on output or use with
231 * function chaining. (See User Guide for details.)
232 * @return the requested UNormalizer2, if successful
233 * @stable ICU 4.4
234 */
235U_STABLE UNormalizer2 * U_EXPORT2
236unorm2_openFiltered(const UNormalizer2 *norm2, const USet *filterSet, UErrorCode *pErrorCode);
237
238/**
239 * Closes a UNormalizer2 instance from unorm2_openFiltered().
240 * Do not close instances from unorm2_getInstance()!
241 * @param norm2 UNormalizer2 instance to be closed
242 * @stable ICU 4.4
243 */
244U_STABLE void U_EXPORT2
245unorm2_close(UNormalizer2 *norm2);
246
247#if U_SHOW_CPLUSPLUS_API
248
249U_NAMESPACE_BEGIN
250
251/**
252 * \class LocalUNormalizer2Pointer
253 * "Smart pointer" class, closes a UNormalizer2 via unorm2_close().
254 * For most methods see the LocalPointerBase base class.
255 *
256 * @see LocalPointerBase
257 * @see LocalPointer
258 * @stable ICU 4.4
259 */
260U_DEFINE_LOCAL_OPEN_POINTER(LocalUNormalizer2Pointer, UNormalizer2, unorm2_close);
261
262U_NAMESPACE_END
263
f3c0d7a5 264#endif // U_SHOW_CPLUSPLUS_API
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265
266/**
267 * Writes the normalized form of the source string to the destination string
268 * (replacing its contents) and returns the length of the destination string.
269 * The source and destination strings must be different buffers.
270 * @param norm2 UNormalizer2 instance
271 * @param src source string
272 * @param length length of the source string, or -1 if NUL-terminated
273 * @param dest destination string; its contents is replaced with normalized src
274 * @param capacity number of UChars that can be written to dest
275 * @param pErrorCode Standard ICU error code. Its input value must
276 * pass the U_SUCCESS() test, or else the function returns
277 * immediately. Check for U_FAILURE() on output or use with
278 * function chaining. (See User Guide for details.)
279 * @return dest
280 * @stable ICU 4.4
281 */
282U_STABLE int32_t U_EXPORT2
283unorm2_normalize(const UNormalizer2 *norm2,
284 const UChar *src, int32_t length,
285 UChar *dest, int32_t capacity,
286 UErrorCode *pErrorCode);
287/**
288 * Appends the normalized form of the second string to the first string
289 * (merging them at the boundary) and returns the length of the first string.
290 * The result is normalized if the first string was normalized.
291 * The first and second strings must be different buffers.
292 * @param norm2 UNormalizer2 instance
293 * @param first string, should be normalized
294 * @param firstLength length of the first string, or -1 if NUL-terminated
295 * @param firstCapacity number of UChars that can be written to first
296 * @param second string, will be normalized
297 * @param secondLength length of the source string, or -1 if NUL-terminated
298 * @param pErrorCode Standard ICU error code. Its input value must
299 * pass the U_SUCCESS() test, or else the function returns
300 * immediately. Check for U_FAILURE() on output or use with
301 * function chaining. (See User Guide for details.)
302 * @return first
303 * @stable ICU 4.4
304 */
305U_STABLE int32_t U_EXPORT2
306unorm2_normalizeSecondAndAppend(const UNormalizer2 *norm2,
307 UChar *first, int32_t firstLength, int32_t firstCapacity,
308 const UChar *second, int32_t secondLength,
309 UErrorCode *pErrorCode);
310/**
311 * Appends the second string to the first string
312 * (merging them at the boundary) and returns the length of the first string.
313 * The result is normalized if both the strings were normalized.
314 * The first and second strings must be different buffers.
315 * @param norm2 UNormalizer2 instance
316 * @param first string, should be normalized
317 * @param firstLength length of the first string, or -1 if NUL-terminated
318 * @param firstCapacity number of UChars that can be written to first
319 * @param second string, should be normalized
320 * @param secondLength length of the source string, or -1 if NUL-terminated
321 * @param pErrorCode Standard ICU error code. Its input value must
322 * pass the U_SUCCESS() test, or else the function returns
323 * immediately. Check for U_FAILURE() on output or use with
324 * function chaining. (See User Guide for details.)
325 * @return first
326 * @stable ICU 4.4
327 */
328U_STABLE int32_t U_EXPORT2
329unorm2_append(const UNormalizer2 *norm2,
330 UChar *first, int32_t firstLength, int32_t firstCapacity,
331 const UChar *second, int32_t secondLength,
332 UErrorCode *pErrorCode);
333
334/**
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335 * Gets the decomposition mapping of c.
336 * Roughly equivalent to normalizing the String form of c
337 * on a UNORM2_DECOMPOSE UNormalizer2 instance, but much faster, and except that this function
338 * returns a negative value and does not write a string
339 * if c does not have a decomposition mapping in this instance's data.
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340 * This function is independent of the mode of the UNormalizer2.
341 * @param norm2 UNormalizer2 instance
342 * @param c code point
343 * @param decomposition String buffer which will be set to c's
344 * decomposition mapping, if there is one.
345 * @param capacity number of UChars that can be written to decomposition
346 * @param pErrorCode Standard ICU error code. Its input value must
347 * pass the U_SUCCESS() test, or else the function returns
348 * immediately. Check for U_FAILURE() on output or use with
349 * function chaining. (See User Guide for details.)
350 * @return the non-negative length of c's decomposition, if there is one; otherwise a negative value
4388f060 351 * @stable ICU 4.6
729e4ab9 352 */
51004dcb 353U_STABLE int32_t U_EXPORT2
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354unorm2_getDecomposition(const UNormalizer2 *norm2,
355 UChar32 c, UChar *decomposition, int32_t capacity,
356 UErrorCode *pErrorCode);
357
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358/**
359 * Gets the raw decomposition mapping of c.
360 *
361 * This is similar to the unorm2_getDecomposition() function but returns the
362 * raw decomposition mapping as specified in UnicodeData.txt or
363 * (for custom data) in the mapping files processed by the gennorm2 tool.
364 * By contrast, unorm2_getDecomposition() returns the processed,
365 * recursively-decomposed version of this mapping.
366 *
367 * When used on a standard NFKC Normalizer2 instance,
368 * unorm2_getRawDecomposition() returns the Unicode Decomposition_Mapping (dm) property.
369 *
370 * When used on a standard NFC Normalizer2 instance,
371 * it returns the Decomposition_Mapping only if the Decomposition_Type (dt) is Canonical (Can);
372 * in this case, the result contains either one or two code points (=1..4 UChars).
373 *
374 * This function is independent of the mode of the UNormalizer2.
375 * @param norm2 UNormalizer2 instance
376 * @param c code point
377 * @param decomposition String buffer which will be set to c's
378 * raw decomposition mapping, if there is one.
379 * @param capacity number of UChars that can be written to decomposition
380 * @param pErrorCode Standard ICU error code. Its input value must
381 * pass the U_SUCCESS() test, or else the function returns
382 * immediately. Check for U_FAILURE() on output or use with
383 * function chaining. (See User Guide for details.)
384 * @return the non-negative length of c's raw decomposition, if there is one; otherwise a negative value
51004dcb 385 * @stable ICU 49
4388f060 386 */
51004dcb 387U_STABLE int32_t U_EXPORT2
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388unorm2_getRawDecomposition(const UNormalizer2 *norm2,
389 UChar32 c, UChar *decomposition, int32_t capacity,
390 UErrorCode *pErrorCode);
391
392/**
393 * Performs pairwise composition of a & b and returns the composite if there is one.
394 *
395 * Returns a composite code point c only if c has a two-way mapping to a+b.
396 * In standard Unicode normalization, this means that
397 * c has a canonical decomposition to a+b
398 * and c does not have the Full_Composition_Exclusion property.
399 *
400 * This function is independent of the mode of the UNormalizer2.
401 * @param norm2 UNormalizer2 instance
402 * @param a A (normalization starter) code point.
403 * @param b Another code point.
404 * @return The non-negative composite code point if there is one; otherwise a negative value.
51004dcb 405 * @stable ICU 49
4388f060 406 */
51004dcb 407U_STABLE UChar32 U_EXPORT2
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408unorm2_composePair(const UNormalizer2 *norm2, UChar32 a, UChar32 b);
409
410/**
411 * Gets the combining class of c.
412 * The default implementation returns 0
413 * but all standard implementations return the Unicode Canonical_Combining_Class value.
414 * @param norm2 UNormalizer2 instance
415 * @param c code point
416 * @return c's combining class
51004dcb 417 * @stable ICU 49
4388f060 418 */
51004dcb 419U_STABLE uint8_t U_EXPORT2
4388f060 420unorm2_getCombiningClass(const UNormalizer2 *norm2, UChar32 c);
4388f060 421
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422/**
423 * Tests if the string is normalized.
424 * Internally, in cases where the quickCheck() method would return "maybe"
425 * (which is only possible for the two COMPOSE modes) this method
426 * resolves to "yes" or "no" to provide a definitive result,
427 * at the cost of doing more work in those cases.
428 * @param norm2 UNormalizer2 instance
429 * @param s input string
430 * @param length length of the string, or -1 if NUL-terminated
431 * @param pErrorCode Standard ICU error code. Its input value must
432 * pass the U_SUCCESS() test, or else the function returns
433 * immediately. Check for U_FAILURE() on output or use with
434 * function chaining. (See User Guide for details.)
435 * @return TRUE if s is normalized
436 * @stable ICU 4.4
437 */
438U_STABLE UBool U_EXPORT2
439unorm2_isNormalized(const UNormalizer2 *norm2,
440 const UChar *s, int32_t length,
441 UErrorCode *pErrorCode);
442
443/**
444 * Tests if the string is normalized.
445 * For the two COMPOSE modes, the result could be "maybe" in cases that
446 * would take a little more work to resolve definitively.
447 * Use spanQuickCheckYes() and normalizeSecondAndAppend() for a faster
448 * combination of quick check + normalization, to avoid
449 * re-checking the "yes" prefix.
450 * @param norm2 UNormalizer2 instance
451 * @param s input string
452 * @param length length of the string, or -1 if NUL-terminated
453 * @param pErrorCode Standard ICU error code. Its input value must
454 * pass the U_SUCCESS() test, or else the function returns
455 * immediately. Check for U_FAILURE() on output or use with
456 * function chaining. (See User Guide for details.)
457 * @return UNormalizationCheckResult
458 * @stable ICU 4.4
459 */
460U_STABLE UNormalizationCheckResult U_EXPORT2
461unorm2_quickCheck(const UNormalizer2 *norm2,
462 const UChar *s, int32_t length,
463 UErrorCode *pErrorCode);
464
465/**
466 * Returns the end of the normalized substring of the input string.
467 * In other words, with <code>end=spanQuickCheckYes(s, ec);</code>
468 * the substring <code>UnicodeString(s, 0, end)</code>
469 * will pass the quick check with a "yes" result.
470 *
471 * The returned end index is usually one or more characters before the
472 * "no" or "maybe" character: The end index is at a normalization boundary.
473 * (See the class documentation for more about normalization boundaries.)
474 *
475 * When the goal is a normalized string and most input strings are expected
476 * to be normalized already, then call this method,
477 * and if it returns a prefix shorter than the input string,
478 * copy that prefix and use normalizeSecondAndAppend() for the remainder.
479 * @param norm2 UNormalizer2 instance
480 * @param s input string
481 * @param length length of the string, or -1 if NUL-terminated
482 * @param pErrorCode Standard ICU error code. Its input value must
483 * pass the U_SUCCESS() test, or else the function returns
484 * immediately. Check for U_FAILURE() on output or use with
485 * function chaining. (See User Guide for details.)
486 * @return "yes" span end index
487 * @stable ICU 4.4
488 */
489U_STABLE int32_t U_EXPORT2
490unorm2_spanQuickCheckYes(const UNormalizer2 *norm2,
491 const UChar *s, int32_t length,
492 UErrorCode *pErrorCode);
493
494/**
495 * Tests if the character always has a normalization boundary before it,
496 * regardless of context.
497 * For details see the Normalizer2 base class documentation.
498 * @param norm2 UNormalizer2 instance
499 * @param c character to test
500 * @return TRUE if c has a normalization boundary before it
501 * @stable ICU 4.4
502 */
503U_STABLE UBool U_EXPORT2
504unorm2_hasBoundaryBefore(const UNormalizer2 *norm2, UChar32 c);
505
506/**
507 * Tests if the character always has a normalization boundary after it,
508 * regardless of context.
509 * For details see the Normalizer2 base class documentation.
510 * @param norm2 UNormalizer2 instance
511 * @param c character to test
512 * @return TRUE if c has a normalization boundary after it
513 * @stable ICU 4.4
514 */
515U_STABLE UBool U_EXPORT2
516unorm2_hasBoundaryAfter(const UNormalizer2 *norm2, UChar32 c);
517
518/**
519 * Tests if the character is normalization-inert.
520 * For details see the Normalizer2 base class documentation.
521 * @param norm2 UNormalizer2 instance
522 * @param c character to test
523 * @return TRUE if c is normalization-inert
524 * @stable ICU 4.4
525 */
526U_STABLE UBool U_EXPORT2
527unorm2_isInert(const UNormalizer2 *norm2, UChar32 c);
528
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529/**
530 * Option bit for unorm_compare:
531 * Both input strings are assumed to fulfill FCD conditions.
532 * @stable ICU 2.2
533 */
534#define UNORM_INPUT_IS_FCD 0x20000
535
536/**
537 * Option bit for unorm_compare:
538 * Perform case-insensitive comparison.
539 * @stable ICU 2.2
540 */
541#define U_COMPARE_IGNORE_CASE 0x10000
542
543#ifndef U_COMPARE_CODE_POINT_ORDER
544/* see also unistr.h and ustring.h */
545/**
546 * Option bit for u_strCaseCompare, u_strcasecmp, unorm_compare, etc:
547 * Compare strings in code point order instead of code unit order.
548 * @stable ICU 2.2
549 */
550#define U_COMPARE_CODE_POINT_ORDER 0x8000
551#endif
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 */
619U_STABLE int32_t U_EXPORT2
620unorm_compare(const UChar *s1, int32_t length1,
621 const UChar *s2, int32_t length2,
622 uint32_t options,
623 UErrorCode *pErrorCode);
624
729e4ab9
A
625#endif /* !UCONFIG_NO_NORMALIZATION */
626#endif /* __UNORM2_H__ */