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__ */
625