xref: /aosp_15_r20/external/icu/libandroidicu/include/unicode/ustring.h (revision 0e209d3975ff4a8c132096b14b0e9364a753506e)
1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 **********************************************************************
5 *   Copyright (C) 1998-2014, International Business Machines
6 *   Corporation and others.  All Rights Reserved.
7 **********************************************************************
8 *
9 * File ustring.h
10 *
11 * Modification History:
12 *
13 *   Date        Name        Description
14 *   12/07/98    bertrand    Creation.
15 ******************************************************************************
16 */
17 
18 #ifndef USTRING_H
19 #define USTRING_H
20 
21 #include "unicode/utypes.h"
22 #include "unicode/putil.h"
23 #include "unicode/uiter.h"
24 
25 /**
26  * \def UBRK_TYPEDEF_UBREAK_ITERATOR
27  * @internal
28  */
29 
30 #ifndef UBRK_TYPEDEF_UBREAK_ITERATOR
31 #   define UBRK_TYPEDEF_UBREAK_ITERATOR
32 /** Simple declaration for u_strToTitle() to avoid including unicode/ubrk.h. @stable ICU 2.1*/
33     typedef struct UBreakIterator UBreakIterator;
34 #endif
35 
36 /**
37  * \file
38  * \brief C API: Unicode string handling functions
39  *
40  * These C API functions provide general Unicode string handling.
41  *
42  * Some functions are equivalent in name, signature, and behavior to the ANSI C <string.h>
43  * functions. (For example, they do not check for bad arguments like NULL string pointers.)
44  * In some cases, only the thread-safe variant of such a function is implemented here
45  * (see u_strtok_r()).
46  *
47  * Other functions provide more Unicode-specific functionality like locale-specific
48  * upper/lower-casing and string comparison in code point order.
49  *
50  * ICU uses 16-bit Unicode (UTF-16) in the form of arrays of UChar code units.
51  * UTF-16 encodes each Unicode code point with either one or two UChar code units.
52  * (This is the default form of Unicode, and a forward-compatible extension of the original,
53  * fixed-width form that was known as UCS-2. UTF-16 superseded UCS-2 with Unicode 2.0
54  * in 1996.)
55  *
56  * Some APIs accept a 32-bit UChar32 value for a single code point.
57  *
58  * ICU also handles 16-bit Unicode text with unpaired surrogates.
59  * Such text is not well-formed UTF-16.
60  * Code-point-related functions treat unpaired surrogates as surrogate code points,
61  * i.e., as separate units.
62  *
63  * Although UTF-16 is a variable-width encoding form (like some legacy multi-byte encodings),
64  * it is much more efficient even for random access because the code unit values
65  * for single-unit characters vs. lead units vs. trail units are completely disjoint.
66  * This means that it is easy to determine character (code point) boundaries from
67  * random offsets in the string.
68  *
69  * Unicode (UTF-16) string processing is optimized for the single-unit case.
70  * Although it is important to support supplementary characters
71  * (which use pairs of lead/trail code units called "surrogates"),
72  * their occurrence is rare. Almost all characters in modern use require only
73  * a single UChar code unit (i.e., their code point values are <=0xffff).
74  *
75  * For more details see the User Guide Strings chapter (https://unicode-org.github.io/icu/userguide/strings/).
76  * For a discussion of the handling of unpaired surrogates see also
77  * Jitterbug 2145 and its icu mailing list proposal on 2002-sep-18.
78  */
79 
80 /**
81  * Determine the length of an array of UChar.
82  *
83  * @param s The array of UChars, NULL (U+0000) terminated.
84  * @return The number of UChars in <code>chars</code>, minus the terminator.
85  * @stable ICU 2.0
86  */
87 U_CAPI int32_t U_EXPORT2
88 u_strlen(const UChar *s);
89 
90 /**
91  * Count Unicode code points in the length UChar code units of the string.
92  * A code point may occupy either one or two UChar code units.
93  * Counting code points involves reading all code units.
94  *
95  * This functions is basically the inverse of the U16_FWD_N() macro (see utf.h).
96  *
97  * @param s The input string.
98  * @param length The number of UChar code units to be checked, or -1 to count all
99  *               code points before the first NUL (U+0000).
100  * @return The number of code points in the specified code units.
101  * @stable ICU 2.0
102  */
103 U_CAPI int32_t U_EXPORT2
104 u_countChar32(const UChar *s, int32_t length);
105 
106 /**
107  * Check if the string contains more Unicode code points than a certain number.
108  * This is more efficient than counting all code points in the entire string
109  * and comparing that number with a threshold.
110  * This function may not need to scan the string at all if the length is known
111  * (not -1 for NUL-termination) and falls within a certain range, and
112  * never needs to count more than 'number+1' code points.
113  * Logically equivalent to (u_countChar32(s, length)>number).
114  * A Unicode code point may occupy either one or two UChar code units.
115  *
116  * @param s The input string.
117  * @param length The length of the string, or -1 if it is NUL-terminated.
118  * @param number The number of code points in the string is compared against
119  *               the 'number' parameter.
120  * @return Boolean value for whether the string contains more Unicode code points
121  *         than 'number'. Same as (u_countChar32(s, length)>number).
122  * @stable ICU 2.4
123  */
124 U_CAPI UBool U_EXPORT2
125 u_strHasMoreChar32Than(const UChar *s, int32_t length, int32_t number);
126 
127 /**
128  * Concatenate two ustrings.  Appends a copy of <code>src</code>,
129  * including the null terminator, to <code>dst</code>. The initial copied
130  * character from <code>src</code> overwrites the null terminator in <code>dst</code>.
131  *
132  * @param dst The destination string.
133  * @param src The source string.
134  * @return A pointer to <code>dst</code>.
135  * @stable ICU 2.0
136  */
137 U_CAPI UChar* U_EXPORT2
138 u_strcat(UChar     *dst,
139     const UChar     *src);
140 
141 /**
142  * Concatenate two ustrings.
143  * Appends at most <code>n</code> characters from <code>src</code> to <code>dst</code>.
144  * Adds a terminating NUL.
145  * If src is too long, then only <code>n-1</code> characters will be copied
146  * before the terminating NUL.
147  * If <code>n&lt;=0</code> then dst is not modified.
148  *
149  * @param dst The destination string.
150  * @param src The source string (can be NULL/invalid if n<=0).
151  * @param n The maximum number of characters to append; no-op if <=0.
152  * @return A pointer to <code>dst</code>.
153  * @stable ICU 2.0
154  */
155 U_CAPI UChar* U_EXPORT2
156 u_strncat(UChar     *dst,
157      const UChar     *src,
158      int32_t     n);
159 
160 /**
161  * Find the first occurrence of a substring in a string.
162  * The substring is found at code point boundaries.
163  * That means that if the substring begins with
164  * a trail surrogate or ends with a lead surrogate,
165  * then it is found only if these surrogates stand alone in the text.
166  * Otherwise, the substring edge units would be matched against
167  * halves of surrogate pairs.
168  *
169  * @param s The string to search (NUL-terminated).
170  * @param substring The substring to find (NUL-terminated).
171  * @return A pointer to the first occurrence of <code>substring</code> in <code>s</code>,
172  *         or <code>s</code> itself if the <code>substring</code> is empty,
173  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
174  * @stable ICU 2.0
175  *
176  * @see u_strrstr
177  * @see u_strFindFirst
178  * @see u_strFindLast
179  */
180 U_CAPI UChar * U_EXPORT2
181 u_strstr(const UChar *s, const UChar *substring);
182 
183 /**
184  * Find the first occurrence of a substring in a string.
185  * The substring is found at code point boundaries.
186  * That means that if the substring begins with
187  * a trail surrogate or ends with a lead surrogate,
188  * then it is found only if these surrogates stand alone in the text.
189  * Otherwise, the substring edge units would be matched against
190  * halves of surrogate pairs.
191  *
192  * @param s The string to search.
193  * @param length The length of s (number of UChars), or -1 if it is NUL-terminated.
194  * @param substring The substring to find (NUL-terminated).
195  * @param subLength The length of substring (number of UChars), or -1 if it is NUL-terminated.
196  * @return A pointer to the first occurrence of <code>substring</code> in <code>s</code>,
197  *         or <code>s</code> itself if the <code>substring</code> is empty,
198  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
199  * @stable ICU 2.4
200  *
201  * @see u_strstr
202  * @see u_strFindLast
203  */
204 U_CAPI UChar * U_EXPORT2
205 u_strFindFirst(const UChar *s, int32_t length, const UChar *substring, int32_t subLength);
206 
207 /**
208  * Find the first occurrence of a BMP code point in a string.
209  * A surrogate code point is found only if its match in the text is not
210  * part of a surrogate pair.
211  * A NUL character is found at the string terminator.
212  *
213  * @param s The string to search (NUL-terminated).
214  * @param c The BMP code point to find.
215  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
216  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
217  * @stable ICU 2.0
218  *
219  * @see u_strchr32
220  * @see u_memchr
221  * @see u_strstr
222  * @see u_strFindFirst
223  */
224 U_CAPI UChar * U_EXPORT2
225 u_strchr(const UChar *s, UChar c);
226 
227 /**
228  * Find the first occurrence of a code point in a string.
229  * A surrogate code point is found only if its match in the text is not
230  * part of a surrogate pair.
231  * A NUL character is found at the string terminator.
232  *
233  * @param s The string to search (NUL-terminated).
234  * @param c The code point to find.
235  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
236  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
237  * @stable ICU 2.0
238  *
239  * @see u_strchr
240  * @see u_memchr32
241  * @see u_strstr
242  * @see u_strFindFirst
243  */
244 U_CAPI UChar * U_EXPORT2
245 u_strchr32(const UChar *s, UChar32 c);
246 
247 /**
248  * Find the last occurrence of a substring in a string.
249  * The substring is found at code point boundaries.
250  * That means that if the substring begins with
251  * a trail surrogate or ends with a lead surrogate,
252  * then it is found only if these surrogates stand alone in the text.
253  * Otherwise, the substring edge units would be matched against
254  * halves of surrogate pairs.
255  *
256  * @param s The string to search (NUL-terminated).
257  * @param substring The substring to find (NUL-terminated).
258  * @return A pointer to the last occurrence of <code>substring</code> in <code>s</code>,
259  *         or <code>s</code> itself if the <code>substring</code> is empty,
260  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
261  * @stable ICU 2.4
262  *
263  * @see u_strstr
264  * @see u_strFindFirst
265  * @see u_strFindLast
266  */
267 U_CAPI UChar * U_EXPORT2
268 u_strrstr(const UChar *s, const UChar *substring);
269 
270 /**
271  * Find the last occurrence of a substring in a string.
272  * The substring is found at code point boundaries.
273  * That means that if the substring begins with
274  * a trail surrogate or ends with a lead surrogate,
275  * then it is found only if these surrogates stand alone in the text.
276  * Otherwise, the substring edge units would be matched against
277  * halves of surrogate pairs.
278  *
279  * @param s The string to search.
280  * @param length The length of s (number of UChars), or -1 if it is NUL-terminated.
281  * @param substring The substring to find (NUL-terminated).
282  * @param subLength The length of substring (number of UChars), or -1 if it is NUL-terminated.
283  * @return A pointer to the last occurrence of <code>substring</code> in <code>s</code>,
284  *         or <code>s</code> itself if the <code>substring</code> is empty,
285  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
286  * @stable ICU 2.4
287  *
288  * @see u_strstr
289  * @see u_strFindLast
290  */
291 U_CAPI UChar * U_EXPORT2
292 u_strFindLast(const UChar *s, int32_t length, const UChar *substring, int32_t subLength);
293 
294 /**
295  * Find the last occurrence of a BMP code point in a string.
296  * A surrogate code point is found only if its match in the text is not
297  * part of a surrogate pair.
298  * A NUL character is found at the string terminator.
299  *
300  * @param s The string to search (NUL-terminated).
301  * @param c The BMP code point to find.
302  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
303  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
304  * @stable ICU 2.4
305  *
306  * @see u_strrchr32
307  * @see u_memrchr
308  * @see u_strrstr
309  * @see u_strFindLast
310  */
311 U_CAPI UChar * U_EXPORT2
312 u_strrchr(const UChar *s, UChar c);
313 
314 /**
315  * Find the last occurrence of a code point in a string.
316  * A surrogate code point is found only if its match in the text is not
317  * part of a surrogate pair.
318  * A NUL character is found at the string terminator.
319  *
320  * @param s The string to search (NUL-terminated).
321  * @param c The code point to find.
322  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
323  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
324  * @stable ICU 2.4
325  *
326  * @see u_strrchr
327  * @see u_memchr32
328  * @see u_strrstr
329  * @see u_strFindLast
330  */
331 U_CAPI UChar * U_EXPORT2
332 u_strrchr32(const UChar *s, UChar32 c);
333 
334 /**
335  * Locates the first occurrence in the string <code>string</code> of any of the characters
336  * in the string <code>matchSet</code>.
337  * Works just like C's strpbrk but with Unicode.
338  *
339  * @param string The string in which to search, NUL-terminated.
340  * @param matchSet A NUL-terminated string defining a set of code points
341  *                 for which to search in the text string.
342  * @return A pointer to the  character in <code>string</code> that matches one of the
343  *         characters in <code>matchSet</code>, or NULL if no such character is found.
344  * @stable ICU 2.0
345  */
346 U_CAPI UChar * U_EXPORT2
347 u_strpbrk(const UChar *string, const UChar *matchSet);
348 
349 /**
350  * Returns the number of consecutive characters in <code>string</code>,
351  * beginning with the first, that do not occur somewhere in <code>matchSet</code>.
352  * Works just like C's strcspn but with Unicode.
353  *
354  * @param string The string in which to search, NUL-terminated.
355  * @param matchSet A NUL-terminated string defining a set of code points
356  *                 for which to search in the text string.
357  * @return The number of initial characters in <code>string</code> that do not
358  *         occur in <code>matchSet</code>.
359  * @see u_strspn
360  * @stable ICU 2.0
361  */
362 U_CAPI int32_t U_EXPORT2
363 u_strcspn(const UChar *string, const UChar *matchSet);
364 
365 /**
366  * Returns the number of consecutive characters in <code>string</code>,
367  * beginning with the first, that occur somewhere in <code>matchSet</code>.
368  * Works just like C's strspn but with Unicode.
369  *
370  * @param string The string in which to search, NUL-terminated.
371  * @param matchSet A NUL-terminated string defining a set of code points
372  *                 for which to search in the text string.
373  * @return The number of initial characters in <code>string</code> that do
374  *         occur in <code>matchSet</code>.
375  * @see u_strcspn
376  * @stable ICU 2.0
377  */
378 U_CAPI int32_t U_EXPORT2
379 u_strspn(const UChar *string, const UChar *matchSet);
380 
381 /**
382  * The string tokenizer API allows an application to break a string into
383  * tokens. Unlike strtok(), the saveState (the current pointer within the
384  * original string) is maintained in saveState. In the first call, the
385  * argument src is a pointer to the string. In subsequent calls to
386  * return successive tokens of that string, src must be specified as
387  * NULL. The value saveState is set by this function to maintain the
388  * function's position within the string, and on each subsequent call
389  * you must give this argument the same variable. This function does
390  * handle surrogate pairs. This function is similar to the strtok_r()
391  * the POSIX Threads Extension (1003.1c-1995) version.
392  *
393  * @param src String containing token(s). This string will be modified.
394  *            After the first call to u_strtok_r(), this argument must
395  *            be NULL to get to the next token.
396  * @param delim Set of delimiter characters (Unicode code points).
397  * @param saveState The current pointer within the original string,
398  *              which is set by this function. The saveState
399  *              parameter should the address of a local variable of type
400  *              UChar *. (i.e. defined "UChar *myLocalSaveState" and use
401  *              &myLocalSaveState for this parameter).
402  * @return A pointer to the next token found in src, or NULL
403  *         when there are no more tokens.
404  * @stable ICU 2.0
405  */
406 U_CAPI UChar * U_EXPORT2
407 u_strtok_r(UChar    *src,
408      const UChar    *delim,
409            UChar   **saveState);
410 
411 /**
412  * Compare two Unicode strings for bitwise equality (code unit order).
413  *
414  * @param s1 A string to compare.
415  * @param s2 A string to compare.
416  * @return 0 if <code>s1</code> and <code>s2</code> are bitwise equal; a negative
417  * value if <code>s1</code> is bitwise less than <code>s2,</code>; a positive
418  * value if <code>s1</code> is bitwise greater than <code>s2</code>.
419  * @stable ICU 2.0
420  */
421 U_CAPI int32_t  U_EXPORT2
422 u_strcmp(const UChar     *s1,
423          const UChar     *s2);
424 
425 /**
426  * Compare two Unicode strings in code point order.
427  * See u_strCompare for details.
428  *
429  * @param s1 A string to compare.
430  * @param s2 A string to compare.
431  * @return a negative/zero/positive integer corresponding to whether
432  * the first string is less than/equal to/greater than the second one
433  * in code point order
434  * @stable ICU 2.0
435  */
436 U_CAPI int32_t U_EXPORT2
437 u_strcmpCodePointOrder(const UChar *s1, const UChar *s2);
438 
439 /**
440  * Compare two Unicode strings (binary order).
441  *
442  * The comparison can be done in code unit order or in code point order.
443  * They differ only in UTF-16 when
444  * comparing supplementary code points (U+10000..U+10ffff)
445  * to BMP code points near the end of the BMP (i.e., U+e000..U+ffff).
446  * In code unit order, high BMP code points sort after supplementary code points
447  * because they are stored as pairs of surrogates which are at U+d800..U+dfff.
448  *
449  * This functions works with strings of different explicitly specified lengths
450  * unlike the ANSI C-like u_strcmp() and u_memcmp() etc.
451  * NUL-terminated strings are possible with length arguments of -1.
452  *
453  * @param s1 First source string.
454  * @param length1 Length of first source string, or -1 if NUL-terminated.
455  *
456  * @param s2 Second source string.
457  * @param length2 Length of second source string, or -1 if NUL-terminated.
458  *
459  * @param codePointOrder Choose between code unit order (false)
460  *                       and code point order (true).
461  *
462  * @return <0 or 0 or >0 as usual for string comparisons
463  *
464  * @stable ICU 2.2
465  */
466 U_CAPI int32_t U_EXPORT2
467 u_strCompare(const UChar *s1, int32_t length1,
468              const UChar *s2, int32_t length2,
469              UBool codePointOrder);
470 
471 /**
472  * Compare two Unicode strings (binary order)
473  * as presented by UCharIterator objects.
474  * Works otherwise just like u_strCompare().
475  *
476  * Both iterators are reset to their start positions.
477  * When the function returns, it is undefined where the iterators
478  * have stopped.
479  *
480  * @param iter1 First source string iterator.
481  * @param iter2 Second source string iterator.
482  * @param codePointOrder Choose between code unit order (false)
483  *                       and code point order (true).
484  *
485  * @return <0 or 0 or >0 as usual for string comparisons
486  *
487  * @see u_strCompare
488  *
489  * @stable ICU 2.6
490  */
491 U_CAPI int32_t U_EXPORT2
492 u_strCompareIter(UCharIterator *iter1, UCharIterator *iter2, UBool codePointOrder);
493 
494 /**
495  * Compare two strings case-insensitively using full case folding.
496  * This is equivalent to
497  *   u_strCompare(u_strFoldCase(s1, options),
498  *                u_strFoldCase(s2, options),
499  *                (options&U_COMPARE_CODE_POINT_ORDER)!=0).
500  *
501  * The comparison can be done in UTF-16 code unit order or in code point order.
502  * They differ only when comparing supplementary code points (U+10000..U+10ffff)
503  * to BMP code points near the end of the BMP (i.e., U+e000..U+ffff).
504  * In code unit order, high BMP code points sort after supplementary code points
505  * because they are stored as pairs of surrogates which are at U+d800..U+dfff.
506  *
507  * This functions works with strings of different explicitly specified lengths
508  * unlike the ANSI C-like u_strcmp() and u_memcmp() etc.
509  * NUL-terminated strings are possible with length arguments of -1.
510  *
511  * @param s1 First source string.
512  * @param length1 Length of first source string, or -1 if NUL-terminated.
513  *
514  * @param s2 Second source string.
515  * @param length2 Length of second source string, or -1 if NUL-terminated.
516  *
517  * @param options A bit set of options:
518  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
519  *     Comparison in code unit order with default case folding.
520  *
521  *   - U_COMPARE_CODE_POINT_ORDER
522  *     Set to choose code point order instead of code unit order
523  *     (see u_strCompare for details).
524  *
525  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
526  *
527  * @param pErrorCode Must be a valid pointer to an error code value,
528  *                  which must not indicate a failure before the function call.
529  *
530  * @return <0 or 0 or >0 as usual for string comparisons
531  *
532  * @stable ICU 2.2
533  */
534 U_CAPI int32_t U_EXPORT2
535 u_strCaseCompare(const UChar *s1, int32_t length1,
536                  const UChar *s2, int32_t length2,
537                  uint32_t options,
538                  UErrorCode *pErrorCode);
539 
540 /**
541  * Compare two ustrings for bitwise equality.
542  * Compares at most <code>n</code> characters.
543  *
544  * @param ucs1 A string to compare (can be NULL/invalid if n<=0).
545  * @param ucs2 A string to compare (can be NULL/invalid if n<=0).
546  * @param n The maximum number of characters to compare; always returns 0 if n<=0.
547  * @return 0 if <code>s1</code> and <code>s2</code> are bitwise equal; a negative
548  * value if <code>s1</code> is bitwise less than <code>s2</code>; a positive
549  * value if <code>s1</code> is bitwise greater than <code>s2</code>.
550  * @stable ICU 2.0
551  */
552 U_CAPI int32_t U_EXPORT2
553 u_strncmp(const UChar     *ucs1,
554      const UChar     *ucs2,
555      int32_t     n);
556 
557 /**
558  * Compare two Unicode strings in code point order.
559  * This is different in UTF-16 from u_strncmp() if supplementary characters are present.
560  * For details, see u_strCompare().
561  *
562  * @param s1 A string to compare.
563  * @param s2 A string to compare.
564  * @param n The maximum number of characters to compare.
565  * @return a negative/zero/positive integer corresponding to whether
566  * the first string is less than/equal to/greater than the second one
567  * in code point order
568  * @stable ICU 2.0
569  */
570 U_CAPI int32_t U_EXPORT2
571 u_strncmpCodePointOrder(const UChar *s1, const UChar *s2, int32_t n);
572 
573 /**
574  * Compare two strings case-insensitively using full case folding.
575  * This is equivalent to u_strcmp(u_strFoldCase(s1, options), u_strFoldCase(s2, options)).
576  *
577  * @param s1 A string to compare.
578  * @param s2 A string to compare.
579  * @param options A bit set of options:
580  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
581  *     Comparison in code unit order with default case folding.
582  *
583  *   - U_COMPARE_CODE_POINT_ORDER
584  *     Set to choose code point order instead of code unit order
585  *     (see u_strCompare for details).
586  *
587  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
588  *
589  * @return A negative, zero, or positive integer indicating the comparison result.
590  * @stable ICU 2.0
591  */
592 U_CAPI int32_t U_EXPORT2
593 u_strcasecmp(const UChar *s1, const UChar *s2, uint32_t options);
594 
595 /**
596  * Compare two strings case-insensitively using full case folding.
597  * This is equivalent to u_strcmp(u_strFoldCase(s1, at most n, options),
598  * u_strFoldCase(s2, at most n, options)).
599  *
600  * @param s1 A string to compare.
601  * @param s2 A string to compare.
602  * @param n The maximum number of characters each string to case-fold and then compare.
603  * @param options A bit set of options:
604  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
605  *     Comparison in code unit order with default case folding.
606  *
607  *   - U_COMPARE_CODE_POINT_ORDER
608  *     Set to choose code point order instead of code unit order
609  *     (see u_strCompare for details).
610  *
611  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
612  *
613  * @return A negative, zero, or positive integer indicating the comparison result.
614  * @stable ICU 2.0
615  */
616 U_CAPI int32_t U_EXPORT2
617 u_strncasecmp(const UChar *s1, const UChar *s2, int32_t n, uint32_t options);
618 
619 /**
620  * Compare two strings case-insensitively using full case folding.
621  * This is equivalent to u_strcmp(u_strFoldCase(s1, n, options),
622  * u_strFoldCase(s2, n, options)).
623  *
624  * @param s1 A string to compare.
625  * @param s2 A string to compare.
626  * @param length The number of characters in each string to case-fold and then compare.
627  * @param options A bit set of options:
628  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
629  *     Comparison in code unit order with default case folding.
630  *
631  *   - U_COMPARE_CODE_POINT_ORDER
632  *     Set to choose code point order instead of code unit order
633  *     (see u_strCompare for details).
634  *
635  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
636  *
637  * @return A negative, zero, or positive integer indicating the comparison result.
638  * @stable ICU 2.0
639  */
640 U_CAPI int32_t U_EXPORT2
641 u_memcasecmp(const UChar *s1, const UChar *s2, int32_t length, uint32_t options);
642 
643 /**
644  * Copy a ustring. Adds a null terminator.
645  *
646  * @param dst The destination string.
647  * @param src The source string.
648  * @return A pointer to <code>dst</code>.
649  * @stable ICU 2.0
650  */
651 U_CAPI UChar* U_EXPORT2
652 u_strcpy(UChar     *dst,
653     const UChar     *src);
654 
655 /**
656  * Copy a ustring.
657  * Copies at most <code>n</code> characters.  The result will be null terminated
658  * if the length of <code>src</code> is less than <code>n</code>.
659  *
660  * @param dst The destination string.
661  * @param src The source string (can be NULL/invalid if n<=0).
662  * @param n The maximum number of characters to copy; no-op if <=0.
663  * @return A pointer to <code>dst</code>.
664  * @stable ICU 2.0
665  */
666 U_CAPI UChar* U_EXPORT2
667 u_strncpy(UChar     *dst,
668      const UChar     *src,
669      int32_t     n);
670 
671 #if !UCONFIG_NO_CONVERSION
672 
673 /**
674  * Copy a byte string encoded in the default codepage to a ustring.
675  * Adds a null terminator.
676  * Performs a host byte to UChar conversion
677  *
678  * @param dst The destination string.
679  * @param src The source string.
680  * @return A pointer to <code>dst</code>.
681  * @stable ICU 2.0
682  */
683 U_CAPI UChar* U_EXPORT2 u_uastrcpy(UChar *dst,
684                const char *src );
685 
686 /**
687  * Copy a byte string encoded in the default codepage to a ustring.
688  * Copies at most <code>n</code> characters.  The result will be null terminated
689  * if the length of <code>src</code> is less than <code>n</code>.
690  * Performs a host byte to UChar conversion
691  *
692  * @param dst The destination string.
693  * @param src The source string.
694  * @param n The maximum number of characters to copy.
695  * @return A pointer to <code>dst</code>.
696  * @stable ICU 2.0
697  */
698 U_CAPI UChar* U_EXPORT2 u_uastrncpy(UChar *dst,
699             const char *src,
700             int32_t n);
701 
702 /**
703  * Copy ustring to a byte string encoded in the default codepage.
704  * Adds a null terminator.
705  * Performs a UChar to host byte conversion
706  *
707  * @param dst The destination string.
708  * @param src The source string.
709  * @return A pointer to <code>dst</code>.
710  * @stable ICU 2.0
711  */
712 U_CAPI char* U_EXPORT2 u_austrcpy(char *dst,
713             const UChar *src );
714 
715 /**
716  * Copy ustring to a byte string encoded in the default codepage.
717  * Copies at most <code>n</code> characters.  The result will be null terminated
718  * if the length of <code>src</code> is less than <code>n</code>.
719  * Performs a UChar to host byte conversion
720  *
721  * @param dst The destination string.
722  * @param src The source string.
723  * @param n The maximum number of characters to copy.
724  * @return A pointer to <code>dst</code>.
725  * @stable ICU 2.0
726  */
727 U_CAPI char* U_EXPORT2 u_austrncpy(char *dst,
728             const UChar *src,
729             int32_t n );
730 
731 #endif
732 
733 /**
734  * Synonym for memcpy(), but with UChars only.
735  * @param dest The destination string
736  * @param src The source string (can be NULL/invalid if count<=0)
737  * @param count The number of characters to copy; no-op if <=0
738  * @return A pointer to <code>dest</code>
739  * @stable ICU 2.0
740  */
741 U_CAPI UChar* U_EXPORT2
742 u_memcpy(UChar *dest, const UChar *src, int32_t count);
743 
744 /**
745  * Synonym for memmove(), but with UChars only.
746  * @param dest The destination string
747  * @param src The source string (can be NULL/invalid if count<=0)
748  * @param count The number of characters to move; no-op if <=0
749  * @return A pointer to <code>dest</code>
750  * @stable ICU 2.0
751  */
752 U_CAPI UChar* U_EXPORT2
753 u_memmove(UChar *dest, const UChar *src, int32_t count);
754 
755 /**
756  * Initialize <code>count</code> characters of <code>dest</code> to <code>c</code>.
757  *
758  * @param dest The destination string.
759  * @param c The character to initialize the string.
760  * @param count The maximum number of characters to set.
761  * @return A pointer to <code>dest</code>.
762  * @stable ICU 2.0
763  */
764 U_CAPI UChar* U_EXPORT2
765 u_memset(UChar *dest, UChar c, int32_t count);
766 
767 /**
768  * Compare the first <code>count</code> UChars of each buffer.
769  *
770  * @param buf1 The first string to compare.
771  * @param buf2 The second string to compare.
772  * @param count The maximum number of UChars to compare.
773  * @return When buf1 < buf2, a negative number is returned.
774  *      When buf1 == buf2, 0 is returned.
775  *      When buf1 > buf2, a positive number is returned.
776  * @stable ICU 2.0
777  */
778 U_CAPI int32_t U_EXPORT2
779 u_memcmp(const UChar *buf1, const UChar *buf2, int32_t count);
780 
781 /**
782  * Compare two Unicode strings in code point order.
783  * This is different in UTF-16 from u_memcmp() if supplementary characters are present.
784  * For details, see u_strCompare().
785  *
786  * @param s1 A string to compare.
787  * @param s2 A string to compare.
788  * @param count The maximum number of characters to compare.
789  * @return a negative/zero/positive integer corresponding to whether
790  * the first string is less than/equal to/greater than the second one
791  * in code point order
792  * @stable ICU 2.0
793  */
794 U_CAPI int32_t U_EXPORT2
795 u_memcmpCodePointOrder(const UChar *s1, const UChar *s2, int32_t count);
796 
797 /**
798  * Find the first occurrence of a BMP code point in a string.
799  * A surrogate code point is found only if its match in the text is not
800  * part of a surrogate pair.
801  * A NUL character is found at the string terminator.
802  *
803  * @param s The string to search (contains <code>count</code> UChars).
804  * @param c The BMP code point to find.
805  * @param count The length of the string.
806  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
807  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
808  * @stable ICU 2.0
809  *
810  * @see u_strchr
811  * @see u_memchr32
812  * @see u_strFindFirst
813  */
814 U_CAPI UChar* U_EXPORT2
815 u_memchr(const UChar *s, UChar c, int32_t count);
816 
817 /**
818  * Find the first occurrence of a code point in a string.
819  * A surrogate code point is found only if its match in the text is not
820  * part of a surrogate pair.
821  * A NUL character is found at the string terminator.
822  *
823  * @param s The string to search (contains <code>count</code> UChars).
824  * @param c The code point to find.
825  * @param count The length of the string.
826  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
827  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
828  * @stable ICU 2.0
829  *
830  * @see u_strchr32
831  * @see u_memchr
832  * @see u_strFindFirst
833  */
834 U_CAPI UChar* U_EXPORT2
835 u_memchr32(const UChar *s, UChar32 c, int32_t count);
836 
837 /**
838  * Find the last occurrence of a BMP code point in a string.
839  * A surrogate code point is found only if its match in the text is not
840  * part of a surrogate pair.
841  * A NUL character is found at the string terminator.
842  *
843  * @param s The string to search (contains <code>count</code> UChars).
844  * @param c The BMP code point to find.
845  * @param count The length of the string.
846  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
847  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
848  * @stable ICU 2.4
849  *
850  * @see u_strrchr
851  * @see u_memrchr32
852  * @see u_strFindLast
853  */
854 U_CAPI UChar* U_EXPORT2
855 u_memrchr(const UChar *s, UChar c, int32_t count);
856 
857 /**
858  * Find the last occurrence of a code point in a string.
859  * A surrogate code point is found only if its match in the text is not
860  * part of a surrogate pair.
861  * A NUL character is found at the string terminator.
862  *
863  * @param s The string to search (contains <code>count</code> UChars).
864  * @param c The code point to find.
865  * @param count The length of the string.
866  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
867  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
868  * @stable ICU 2.4
869  *
870  * @see u_strrchr32
871  * @see u_memrchr
872  * @see u_strFindLast
873  */
874 U_CAPI UChar* U_EXPORT2
875 u_memrchr32(const UChar *s, UChar32 c, int32_t count);
876 
877 /**
878  * Unicode String literals in C.
879  * We need one macro to declare a variable for the string
880  * and to statically preinitialize it if possible,
881  * and a second macro to dynamically initialize such a string variable if necessary.
882  *
883  * The macros are defined for maximum performance.
884  * They work only for strings that contain "invariant characters", i.e.,
885  * only latin letters, digits, and some punctuation.
886  * See utypes.h for details.
887  *
888  * A pair of macros for a single string must be used with the same
889  * parameters.
890  * The string parameter must be a C string literal.
891  * The length of the string, not including the terminating
892  * `NUL`, must be specified as a constant.
893  * The U_STRING_DECL macro should be invoked exactly once for one
894  * such string variable before it is used.
895  *
896  * Usage:
897  *
898  *     U_STRING_DECL(ustringVar1, "Quick-Fox 2", 11);
899  *     U_STRING_DECL(ustringVar2, "jumps 5%", 8);
900  *     static UBool didInit=false;
901  *
902  *     int32_t function() {
903  *         if(!didInit) {
904  *             U_STRING_INIT(ustringVar1, "Quick-Fox 2", 11);
905  *             U_STRING_INIT(ustringVar2, "jumps 5%", 8);
906  *             didInit=true;
907  *         }
908  *         return u_strcmp(ustringVar1, ustringVar2);
909  *     }
910  *
911  * Note that the macros will NOT consistently work if their argument is another #`define`.
912  * The following will not work on all platforms, don't use it.
913  *
914  *     #define GLUCK "Mr. Gluck"
915  *     U_STRING_DECL(var, GLUCK, 9)
916  *     U_STRING_INIT(var, GLUCK, 9)
917  *
918  * Instead, use the string literal "Mr. Gluck"  as the argument to both macro
919  * calls.
920  *
921  *
922  * @stable ICU 2.0
923  */
924 #if defined(U_DECLARE_UTF16)
925 #   define U_STRING_DECL(var, cs, length) static const UChar *var=(const UChar *)U_DECLARE_UTF16(cs)
926     /**@stable ICU 2.0 */
927 #   define U_STRING_INIT(var, cs, length)
928 #elif U_SIZEOF_WCHAR_T==U_SIZEOF_UCHAR && (U_CHARSET_FAMILY==U_ASCII_FAMILY || defined(U_WCHAR_IS_UTF16))
929 #   define U_STRING_DECL(var, cs, length) static const UChar var[(length)+1]=L ## cs
930     /**@stable ICU 2.0 */
931 #   define U_STRING_INIT(var, cs, length)
932 #else
933 #   define U_STRING_DECL(var, cs, length) static UChar var[(length)+1]
934     /**@stable ICU 2.0 */
935 #   define U_STRING_INIT(var, cs, length) u_charsToUChars(cs, var, length+1)
936 #endif
937 
938 /**
939  * Unescape a string of characters and write the resulting
940  * Unicode characters to the destination buffer.  The following escape
941  * sequences are recognized:
942  *
943  * \\uhhhh       4 hex digits; h in [0-9A-Fa-f]
944  * \\Uhhhhhhhh   8 hex digits
945  * \\xhh         1-2 hex digits
946  * \\x{h...}     1-8 hex digits
947  * \\ooo         1-3 octal digits; o in [0-7]
948  * \\cX          control-X; X is masked with 0x1F
949  *
950  * as well as the standard ANSI C escapes:
951  *
952  * \\a => U+0007, \\b => U+0008, \\t => U+0009, \\n => U+000A,
953  * \\v => U+000B, \\f => U+000C, \\r => U+000D, \\e => U+001B,
954  * \\&quot; => U+0022, \\' => U+0027, \\? => U+003F, \\\\ => U+005C
955  *
956  * Anything else following a backslash is generically escaped.  For
957  * example, "[a\\-z]" returns "[a-z]".
958  *
959  * If an escape sequence is ill-formed, this method returns an empty
960  * string.  An example of an ill-formed sequence is "\\u" followed by
961  * fewer than 4 hex digits.
962  *
963  * The above characters are recognized in the compiler's codepage,
964  * that is, they are coded as 'u', '\\', etc.  Characters that are
965  * not parts of escape sequences are converted using u_charsToUChars().
966  *
967  * This function is similar to UnicodeString::unescape() but not
968  * identical to it.  The latter takes a source UnicodeString, so it
969  * does escape recognition but no conversion.
970  *
971  * @param src a zero-terminated string of invariant characters
972  * @param dest pointer to buffer to receive converted and unescaped
973  * text and, if there is room, a zero terminator.  May be NULL for
974  * preflighting, in which case no UChars will be written, but the
975  * return value will still be valid.  On error, an empty string is
976  * stored here (if possible).
977  * @param destCapacity the number of UChars that may be written at
978  * dest.  Ignored if dest == NULL.
979  * @return the length of unescaped string.
980  * @see u_unescapeAt
981  * @see UnicodeString#unescape()
982  * @see UnicodeString#unescapeAt()
983  * @stable ICU 2.0
984  */
985 U_CAPI int32_t U_EXPORT2
986 u_unescape(const char *src,
987            UChar *dest, int32_t destCapacity);
988 
989 U_CDECL_BEGIN
990 /**
991  * Callback function for u_unescapeAt() that returns a character of
992  * the source text given an offset and a context pointer.  The context
993  * pointer will be whatever is passed into u_unescapeAt().
994  *
995  * @param offset pointer to the offset that will be passed to u_unescapeAt().
996  * @param context an opaque pointer passed directly into u_unescapeAt()
997  * @return the character represented by the escape sequence at
998  * offset
999  * @see u_unescapeAt
1000  * @stable ICU 2.0
1001  */
1002 typedef UChar (U_CALLCONV *UNESCAPE_CHAR_AT)(int32_t offset, void *context);
1003 U_CDECL_END
1004 
1005 /**
1006  * Unescape a single sequence. The character at offset-1 is assumed
1007  * (without checking) to be a backslash.  This method takes a callback
1008  * pointer to a function that returns the UChar at a given offset.  By
1009  * varying this callback, ICU functions are able to unescape char*
1010  * strings, UnicodeString objects, and UFILE pointers.
1011  *
1012  * If offset is out of range, or if the escape sequence is ill-formed,
1013  * (UChar32)0xFFFFFFFF is returned.  See documentation of u_unescape()
1014  * for a list of recognized sequences.
1015  *
1016  * @param charAt callback function that returns a UChar of the source
1017  * text given an offset and a context pointer.
1018  * @param offset pointer to the offset that will be passed to charAt.
1019  * The offset value will be updated upon return to point after the
1020  * last parsed character of the escape sequence.  On error the offset
1021  * is unchanged.
1022  * @param length the number of characters in the source text.  The
1023  * last character of the source text is considered to be at offset
1024  * length-1.
1025  * @param context an opaque pointer passed directly into charAt.
1026  * @return the character represented by the escape sequence at
1027  * offset, or (UChar32)0xFFFFFFFF on error.
1028  * @see u_unescape()
1029  * @see UnicodeString#unescape()
1030  * @see UnicodeString#unescapeAt()
1031  * @stable ICU 2.0
1032  */
1033 U_CAPI UChar32 U_EXPORT2
1034 u_unescapeAt(UNESCAPE_CHAR_AT charAt,
1035              int32_t *offset,
1036              int32_t length,
1037              void *context);
1038 
1039 /**
1040  * Uppercase the characters in a string.
1041  * Casing is locale-dependent and context-sensitive.
1042  * The result may be longer or shorter than the original.
1043  * The source string and the destination buffer are allowed to overlap.
1044  *
1045  * @param dest      A buffer for the result string. The result will be zero-terminated if
1046  *                  the buffer is large enough.
1047  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
1048  *                  dest may be NULL and the function will only return the length of the result
1049  *                  without writing any of the result string.
1050  * @param src       The original string
1051  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
1052  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
1053  * @param pErrorCode Must be a valid pointer to an error code value,
1054  *                  which must not indicate a failure before the function call.
1055  * @return The length of the result string. It may be greater than destCapacity. In that case,
1056  *         only some of the result was written to the destination buffer.
1057  * @stable ICU 2.0
1058  */
1059 U_CAPI int32_t U_EXPORT2
1060 u_strToUpper(UChar *dest, int32_t destCapacity,
1061              const UChar *src, int32_t srcLength,
1062              const char *locale,
1063              UErrorCode *pErrorCode);
1064 
1065 /**
1066  * Lowercase the characters in a string.
1067  * Casing is locale-dependent and context-sensitive.
1068  * The result may be longer or shorter than the original.
1069  * The source string and the destination buffer are allowed to overlap.
1070  *
1071  * @param dest      A buffer for the result string. The result will be zero-terminated if
1072  *                  the buffer is large enough.
1073  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
1074  *                  dest may be NULL and the function will only return the length of the result
1075  *                  without writing any of the result string.
1076  * @param src       The original string
1077  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
1078  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
1079  * @param pErrorCode Must be a valid pointer to an error code value,
1080  *                  which must not indicate a failure before the function call.
1081  * @return The length of the result string. It may be greater than destCapacity. In that case,
1082  *         only some of the result was written to the destination buffer.
1083  * @stable ICU 2.0
1084  */
1085 U_CAPI int32_t U_EXPORT2
1086 u_strToLower(UChar *dest, int32_t destCapacity,
1087              const UChar *src, int32_t srcLength,
1088              const char *locale,
1089              UErrorCode *pErrorCode);
1090 
1091 #if !UCONFIG_NO_BREAK_ITERATION
1092 
1093 /**
1094  * Titlecase a string.
1095  * Casing is locale-dependent and context-sensitive.
1096  * Titlecasing uses a break iterator to find the first characters of words
1097  * that are to be titlecased. It titlecases those characters and lowercases
1098  * all others.
1099  *
1100  * The titlecase break iterator can be provided to customize for arbitrary
1101  * styles, using rules and dictionaries beyond the standard iterators.
1102  * It may be more efficient to always provide an iterator to avoid
1103  * opening and closing one for each string.
1104  * The standard titlecase iterator for the root locale implements the
1105  * algorithm of Unicode TR 21.
1106  *
1107  * This function uses only the setText(), first() and next() methods of the
1108  * provided break iterator.
1109  *
1110  * The result may be longer or shorter than the original.
1111  * The source string and the destination buffer are allowed to overlap.
1112  *
1113  * @param dest      A buffer for the result string. The result will be zero-terminated if
1114  *                  the buffer is large enough.
1115  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
1116  *                  dest may be NULL and the function will only return the length of the result
1117  *                  without writing any of the result string.
1118  * @param src       The original string
1119  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
1120  * @param titleIter A break iterator to find the first characters of words
1121  *                  that are to be titlecased.
1122  *                  If none is provided (NULL), then a standard titlecase
1123  *                  break iterator is opened.
1124  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
1125  * @param pErrorCode Must be a valid pointer to an error code value,
1126  *                  which must not indicate a failure before the function call.
1127  * @return The length of the result string. It may be greater than destCapacity. In that case,
1128  *         only some of the result was written to the destination buffer.
1129  * @stable ICU 2.1
1130  */
1131 U_CAPI int32_t U_EXPORT2
1132 u_strToTitle(UChar *dest, int32_t destCapacity,
1133              const UChar *src, int32_t srcLength,
1134              UBreakIterator *titleIter,
1135              const char *locale,
1136              UErrorCode *pErrorCode);
1137 
1138 #endif
1139 
1140 /**
1141  * Case-folds the characters in a string.
1142  *
1143  * Case-folding is locale-independent and not context-sensitive,
1144  * but there is an option for whether to include or exclude mappings for dotted I
1145  * and dotless i that are marked with 'T' in CaseFolding.txt.
1146  *
1147  * The result may be longer or shorter than the original.
1148  * The source string and the destination buffer are allowed to overlap.
1149  *
1150  * @param dest      A buffer for the result string. The result will be zero-terminated if
1151  *                  the buffer is large enough.
1152  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
1153  *                  dest may be NULL and the function will only return the length of the result
1154  *                  without writing any of the result string.
1155  * @param src       The original string
1156  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
1157  * @param options   Either U_FOLD_CASE_DEFAULT or U_FOLD_CASE_EXCLUDE_SPECIAL_I
1158  * @param pErrorCode Must be a valid pointer to an error code value,
1159  *                  which must not indicate a failure before the function call.
1160  * @return The length of the result string. It may be greater than destCapacity. In that case,
1161  *         only some of the result was written to the destination buffer.
1162  * @stable ICU 2.0
1163  */
1164 U_CAPI int32_t U_EXPORT2
1165 u_strFoldCase(UChar *dest, int32_t destCapacity,
1166               const UChar *src, int32_t srcLength,
1167               uint32_t options,
1168               UErrorCode *pErrorCode);
1169 
1170 #if defined(U_WCHAR_IS_UTF16) || defined(U_WCHAR_IS_UTF32) || !UCONFIG_NO_CONVERSION
1171 /**
1172  * Convert a UTF-16 string to a wchar_t string.
1173  * If it is known at compile time that wchar_t strings are in UTF-16 or UTF-32, then
1174  * this function simply calls the fast, dedicated function for that.
1175  * Otherwise, two conversions UTF-16 -> default charset -> wchar_t* are performed.
1176  *
1177  * @param dest          A buffer for the result string. The result will be zero-terminated if
1178  *                      the buffer is large enough.
1179  * @param destCapacity  The size of the buffer (number of wchar_t's). If it is 0, then
1180  *                      dest may be NULL and the function will only return the length of the
1181  *                      result without writing any of the result string (pre-flighting).
1182  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1183  *                      pDestLength!=NULL then *pDestLength is always set to the
1184  *                      number of output units corresponding to the transformation of
1185  *                      all the input units, even in case of a buffer overflow.
1186  * @param src           The original source string
1187  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1188  * @param pErrorCode    Must be a valid pointer to an error code value,
1189  *                      which must not indicate a failure before the function call.
1190  * @return The pointer to destination buffer.
1191  * @stable ICU 2.0
1192  */
1193 U_CAPI wchar_t* U_EXPORT2
1194 u_strToWCS(wchar_t *dest,
1195            int32_t destCapacity,
1196            int32_t *pDestLength,
1197            const UChar *src,
1198            int32_t srcLength,
1199            UErrorCode *pErrorCode);
1200 /**
1201  * Convert a wchar_t string to UTF-16.
1202  * If it is known at compile time that wchar_t strings are in UTF-16 or UTF-32, then
1203  * this function simply calls the fast, dedicated function for that.
1204  * Otherwise, two conversions wchar_t* -> default charset -> UTF-16 are performed.
1205  *
1206  * @param dest          A buffer for the result string. The result will be zero-terminated if
1207  *                      the buffer is large enough.
1208  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1209  *                      dest may be NULL and the function will only return the length of the
1210  *                      result without writing any of the result string (pre-flighting).
1211  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1212  *                      pDestLength!=NULL then *pDestLength is always set to the
1213  *                      number of output units corresponding to the transformation of
1214  *                      all the input units, even in case of a buffer overflow.
1215  * @param src           The original source string
1216  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1217  * @param pErrorCode    Must be a valid pointer to an error code value,
1218  *                      which must not indicate a failure before the function call.
1219  * @return The pointer to destination buffer.
1220  * @stable ICU 2.0
1221  */
1222 U_CAPI UChar* U_EXPORT2
1223 u_strFromWCS(UChar   *dest,
1224              int32_t destCapacity,
1225              int32_t *pDestLength,
1226              const wchar_t *src,
1227              int32_t srcLength,
1228              UErrorCode *pErrorCode);
1229 #endif /* defined(U_WCHAR_IS_UTF16) || defined(U_WCHAR_IS_UTF32) || !UCONFIG_NO_CONVERSION */
1230 
1231 /**
1232  * Convert a UTF-16 string to UTF-8.
1233  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
1234  *
1235  * @param dest          A buffer for the result string. The result will be zero-terminated if
1236  *                      the buffer is large enough.
1237  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
1238  *                      dest may be NULL and the function will only return the length of the
1239  *                      result without writing any of the result string (pre-flighting).
1240  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1241  *                      pDestLength!=NULL then *pDestLength is always set to the
1242  *                      number of output units corresponding to the transformation of
1243  *                      all the input units, even in case of a buffer overflow.
1244  * @param src           The original source string
1245  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1246  * @param pErrorCode    Must be a valid pointer to an error code value,
1247  *                      which must not indicate a failure before the function call.
1248  * @return The pointer to destination buffer.
1249  * @stable ICU 2.0
1250  * @see u_strToUTF8WithSub
1251  * @see u_strFromUTF8
1252  */
1253 U_CAPI char* U_EXPORT2
1254 u_strToUTF8(char *dest,
1255             int32_t destCapacity,
1256             int32_t *pDestLength,
1257             const UChar *src,
1258             int32_t srcLength,
1259             UErrorCode *pErrorCode);
1260 
1261 /**
1262  * Convert a UTF-8 string to UTF-16.
1263  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
1264  *
1265  * @param dest          A buffer for the result string. The result will be zero-terminated if
1266  *                      the buffer is large enough.
1267  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1268  *                      dest may be NULL and the function will only return the length of the
1269  *                      result without writing any of the result string (pre-flighting).
1270  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1271  *                      pDestLength!=NULL then *pDestLength is always set to the
1272  *                      number of output units corresponding to the transformation of
1273  *                      all the input units, even in case of a buffer overflow.
1274  * @param src           The original source string
1275  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1276  * @param pErrorCode    Must be a valid pointer to an error code value,
1277  *                      which must not indicate a failure before the function call.
1278  * @return The pointer to destination buffer.
1279  * @stable ICU 2.0
1280  * @see u_strFromUTF8WithSub
1281  * @see u_strFromUTF8Lenient
1282  */
1283 U_CAPI UChar* U_EXPORT2
1284 u_strFromUTF8(UChar *dest,
1285               int32_t destCapacity,
1286               int32_t *pDestLength,
1287               const char *src,
1288               int32_t srcLength,
1289               UErrorCode *pErrorCode);
1290 
1291 /**
1292  * Convert a UTF-16 string to UTF-8.
1293  *
1294  * Same as u_strToUTF8() except for the additional subchar which is output for
1295  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
1296  * With subchar==U_SENTINEL, this function behaves exactly like u_strToUTF8().
1297  *
1298  * @param dest          A buffer for the result string. The result will be zero-terminated if
1299  *                      the buffer is large enough.
1300  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
1301  *                      dest may be NULL and the function will only return the length of the
1302  *                      result without writing any of the result string (pre-flighting).
1303  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1304  *                      pDestLength!=NULL then *pDestLength is always set to the
1305  *                      number of output units corresponding to the transformation of
1306  *                      all the input units, even in case of a buffer overflow.
1307  * @param src           The original source string
1308  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1309  * @param subchar       The substitution character to use in place of an illegal input sequence,
1310  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
1311  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
1312  *                      except for surrogate code points (U+D800..U+DFFF).
1313  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
1314  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
1315  *                      Set to 0 if no substitutions occur or subchar<0.
1316  *                      pNumSubstitutions can be NULL.
1317  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1318  *                      pass the U_SUCCESS() test, or else the function returns
1319  *                      immediately. Check for U_FAILURE() on output or use with
1320  *                      function chaining. (See User Guide for details.)
1321  * @return The pointer to destination buffer.
1322  * @see u_strToUTF8
1323  * @see u_strFromUTF8WithSub
1324  * @stable ICU 3.6
1325  */
1326 U_CAPI char* U_EXPORT2
1327 u_strToUTF8WithSub(char *dest,
1328             int32_t destCapacity,
1329             int32_t *pDestLength,
1330             const UChar *src,
1331             int32_t srcLength,
1332             UChar32 subchar, int32_t *pNumSubstitutions,
1333             UErrorCode *pErrorCode);
1334 
1335 /**
1336  * Convert a UTF-8 string to UTF-16.
1337  *
1338  * Same as u_strFromUTF8() except for the additional subchar which is output for
1339  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
1340  * With subchar==U_SENTINEL, this function behaves exactly like u_strFromUTF8().
1341  *
1342  * @param dest          A buffer for the result string. The result will be zero-terminated if
1343  *                      the buffer is large enough.
1344  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1345  *                      dest may be NULL and the function will only return the length of the
1346  *                      result without writing any of the result string (pre-flighting).
1347  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1348  *                      pDestLength!=NULL then *pDestLength is always set to the
1349  *                      number of output units corresponding to the transformation of
1350  *                      all the input units, even in case of a buffer overflow.
1351  * @param src           The original source string
1352  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1353  * @param subchar       The substitution character to use in place of an illegal input sequence,
1354  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
1355  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
1356  *                      except for surrogate code points (U+D800..U+DFFF).
1357  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
1358  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
1359  *                      Set to 0 if no substitutions occur or subchar<0.
1360  *                      pNumSubstitutions can be NULL.
1361  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1362  *                      pass the U_SUCCESS() test, or else the function returns
1363  *                      immediately. Check for U_FAILURE() on output or use with
1364  *                      function chaining. (See User Guide for details.)
1365  * @return The pointer to destination buffer.
1366  * @see u_strFromUTF8
1367  * @see u_strFromUTF8Lenient
1368  * @see u_strToUTF8WithSub
1369  * @stable ICU 3.6
1370  */
1371 U_CAPI UChar* U_EXPORT2
1372 u_strFromUTF8WithSub(UChar *dest,
1373               int32_t destCapacity,
1374               int32_t *pDestLength,
1375               const char *src,
1376               int32_t srcLength,
1377               UChar32 subchar, int32_t *pNumSubstitutions,
1378               UErrorCode *pErrorCode);
1379 
1380 /**
1381  * Convert a UTF-8 string to UTF-16.
1382  *
1383  * Same as u_strFromUTF8() except that this function is designed to be very fast,
1384  * which it achieves by being lenient about malformed UTF-8 sequences.
1385  * This function is intended for use in environments where UTF-8 text is
1386  * expected to be well-formed.
1387  *
1388  * Its semantics are:
1389  * - Well-formed UTF-8 text is correctly converted to well-formed UTF-16 text.
1390  * - The function will not read beyond the input string, nor write beyond
1391  *   the destCapacity.
1392  * - Malformed UTF-8 results in "garbage" 16-bit Unicode strings which may not
1393  *   be well-formed UTF-16.
1394  *   The function will resynchronize to valid code point boundaries
1395  *   within a small number of code points after an illegal sequence.
1396  * - Non-shortest forms are not detected and will result in "spoofing" output.
1397  *
1398  * For further performance improvement, if srcLength is given (>=0),
1399  * then it must be destCapacity>=srcLength.
1400  *
1401  * There is no inverse u_strToUTF8Lenient() function because there is practically
1402  * no performance gain from not checking that a UTF-16 string is well-formed.
1403  *
1404  * @param dest          A buffer for the result string. The result will be zero-terminated if
1405  *                      the buffer is large enough.
1406  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1407  *                      dest may be NULL and the function will only return the length of the
1408  *                      result without writing any of the result string (pre-flighting).
1409  *                      Unlike for other ICU functions, if srcLength>=0 then it
1410  *                      must be destCapacity>=srcLength.
1411  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1412  *                      pDestLength!=NULL then *pDestLength is always set to the
1413  *                      number of output units corresponding to the transformation of
1414  *                      all the input units, even in case of a buffer overflow.
1415  *                      Unlike for other ICU functions, if srcLength>=0 but
1416  *                      destCapacity<srcLength, then *pDestLength will be set to srcLength
1417  *                      (and U_BUFFER_OVERFLOW_ERROR will be set)
1418  *                      regardless of the actual result length.
1419  * @param src           The original source string
1420  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1421  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1422  *                      pass the U_SUCCESS() test, or else the function returns
1423  *                      immediately. Check for U_FAILURE() on output or use with
1424  *                      function chaining. (See User Guide for details.)
1425  * @return The pointer to destination buffer.
1426  * @see u_strFromUTF8
1427  * @see u_strFromUTF8WithSub
1428  * @see u_strToUTF8WithSub
1429  * @stable ICU 3.6
1430  */
1431 U_CAPI UChar * U_EXPORT2
1432 u_strFromUTF8Lenient(UChar *dest,
1433                      int32_t destCapacity,
1434                      int32_t *pDestLength,
1435                      const char *src,
1436                      int32_t srcLength,
1437                      UErrorCode *pErrorCode);
1438 
1439 /**
1440  * Convert a UTF-16 string to UTF-32.
1441  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
1442  *
1443  * @param dest          A buffer for the result string. The result will be zero-terminated if
1444  *                      the buffer is large enough.
1445  * @param destCapacity  The size of the buffer (number of UChar32s). If it is 0, then
1446  *                      dest may be NULL and the function will only return the length of the
1447  *                      result without writing any of the result string (pre-flighting).
1448  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1449  *                      pDestLength!=NULL then *pDestLength is always set to the
1450  *                      number of output units corresponding to the transformation of
1451  *                      all the input units, even in case of a buffer overflow.
1452  * @param src           The original source string
1453  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1454  * @param pErrorCode    Must be a valid pointer to an error code value,
1455  *                      which must not indicate a failure before the function call.
1456  * @return The pointer to destination buffer.
1457  * @see u_strToUTF32WithSub
1458  * @see u_strFromUTF32
1459  * @stable ICU 2.0
1460  */
1461 U_CAPI UChar32* U_EXPORT2
1462 u_strToUTF32(UChar32 *dest,
1463              int32_t  destCapacity,
1464              int32_t  *pDestLength,
1465              const UChar *src,
1466              int32_t  srcLength,
1467              UErrorCode *pErrorCode);
1468 
1469 /**
1470  * Convert a UTF-32 string to UTF-16.
1471  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
1472  *
1473  * @param dest          A buffer for the result string. The result will be zero-terminated if
1474  *                      the buffer is large enough.
1475  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1476  *                      dest may be NULL and the function will only return the length of the
1477  *                      result without writing any of the result string (pre-flighting).
1478  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1479  *                      pDestLength!=NULL then *pDestLength is always set to the
1480  *                      number of output units corresponding to the transformation of
1481  *                      all the input units, even in case of a buffer overflow.
1482  * @param src           The original source string
1483  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1484  * @param pErrorCode    Must be a valid pointer to an error code value,
1485  *                      which must not indicate a failure before the function call.
1486  * @return The pointer to destination buffer.
1487  * @see u_strFromUTF32WithSub
1488  * @see u_strToUTF32
1489  * @stable ICU 2.0
1490  */
1491 U_CAPI UChar* U_EXPORT2
1492 u_strFromUTF32(UChar   *dest,
1493                int32_t destCapacity,
1494                int32_t *pDestLength,
1495                const UChar32 *src,
1496                int32_t srcLength,
1497                UErrorCode *pErrorCode);
1498 
1499 /**
1500  * Convert a UTF-16 string to UTF-32.
1501  *
1502  * Same as u_strToUTF32() except for the additional subchar which is output for
1503  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
1504  * With subchar==U_SENTINEL, this function behaves exactly like u_strToUTF32().
1505  *
1506  * @param dest          A buffer for the result string. The result will be zero-terminated if
1507  *                      the buffer is large enough.
1508  * @param destCapacity  The size of the buffer (number of UChar32s). If it is 0, then
1509  *                      dest may be NULL and the function will only return the length of the
1510  *                      result without writing any of the result string (pre-flighting).
1511  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1512  *                      pDestLength!=NULL then *pDestLength is always set to the
1513  *                      number of output units corresponding to the transformation of
1514  *                      all the input units, even in case of a buffer overflow.
1515  * @param src           The original source string
1516  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1517  * @param subchar       The substitution character to use in place of an illegal input sequence,
1518  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
1519  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
1520  *                      except for surrogate code points (U+D800..U+DFFF).
1521  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
1522  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
1523  *                      Set to 0 if no substitutions occur or subchar<0.
1524  *                      pNumSubstitutions can be NULL.
1525  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1526  *                      pass the U_SUCCESS() test, or else the function returns
1527  *                      immediately. Check for U_FAILURE() on output or use with
1528  *                      function chaining. (See User Guide for details.)
1529  * @return The pointer to destination buffer.
1530  * @see u_strToUTF32
1531  * @see u_strFromUTF32WithSub
1532  * @stable ICU 4.2
1533  */
1534 U_CAPI UChar32* U_EXPORT2
1535 u_strToUTF32WithSub(UChar32 *dest,
1536              int32_t destCapacity,
1537              int32_t *pDestLength,
1538              const UChar *src,
1539              int32_t srcLength,
1540              UChar32 subchar, int32_t *pNumSubstitutions,
1541              UErrorCode *pErrorCode);
1542 
1543 /**
1544  * Convert a UTF-32 string to UTF-16.
1545  *
1546  * Same as u_strFromUTF32() except for the additional subchar which is output for
1547  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
1548  * With subchar==U_SENTINEL, this function behaves exactly like u_strFromUTF32().
1549  *
1550  * @param dest          A buffer for the result string. The result will be zero-terminated if
1551  *                      the buffer is large enough.
1552  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1553  *                      dest may be NULL and the function will only return the length of the
1554  *                      result without writing any of the result string (pre-flighting).
1555  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1556  *                      pDestLength!=NULL then *pDestLength is always set to the
1557  *                      number of output units corresponding to the transformation of
1558  *                      all the input units, even in case of a buffer overflow.
1559  * @param src           The original source string
1560  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1561  * @param subchar       The substitution character to use in place of an illegal input sequence,
1562  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
1563  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
1564  *                      except for surrogate code points (U+D800..U+DFFF).
1565  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
1566  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
1567  *                      Set to 0 if no substitutions occur or subchar<0.
1568  *                      pNumSubstitutions can be NULL.
1569  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1570  *                      pass the U_SUCCESS() test, or else the function returns
1571  *                      immediately. Check for U_FAILURE() on output or use with
1572  *                      function chaining. (See User Guide for details.)
1573  * @return The pointer to destination buffer.
1574  * @see u_strFromUTF32
1575  * @see u_strToUTF32WithSub
1576  * @stable ICU 4.2
1577  */
1578 U_CAPI UChar* U_EXPORT2
1579 u_strFromUTF32WithSub(UChar *dest,
1580                int32_t destCapacity,
1581                int32_t *pDestLength,
1582                const UChar32 *src,
1583                int32_t srcLength,
1584                UChar32 subchar, int32_t *pNumSubstitutions,
1585                UErrorCode *pErrorCode);
1586 
1587 /**
1588  * Convert a 16-bit Unicode string to Java Modified UTF-8.
1589  * See http://java.sun.com/javase/6/docs/api/java/io/DataInput.html#modified-utf-8
1590  *
1591  * This function behaves according to the documentation for Java DataOutput.writeUTF()
1592  * except that it does not encode the output length in the destination buffer
1593  * and does not have an output length restriction.
1594  * See http://java.sun.com/javase/6/docs/api/java/io/DataOutput.html#writeUTF(java.lang.String)
1595  *
1596  * The input string need not be well-formed UTF-16.
1597  * (Therefore there is no subchar parameter.)
1598  *
1599  * @param dest          A buffer for the result string. The result will be zero-terminated if
1600  *                      the buffer is large enough.
1601  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
1602  *                      dest may be NULL and the function will only return the length of the
1603  *                      result without writing any of the result string (pre-flighting).
1604  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1605  *                      pDestLength!=NULL then *pDestLength is always set to the
1606  *                      number of output units corresponding to the transformation of
1607  *                      all the input units, even in case of a buffer overflow.
1608  * @param src           The original source string
1609  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1610  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1611  *                      pass the U_SUCCESS() test, or else the function returns
1612  *                      immediately. Check for U_FAILURE() on output or use with
1613  *                      function chaining. (See User Guide for details.)
1614  * @return The pointer to destination buffer.
1615  * @stable ICU 4.4
1616  * @see u_strToUTF8WithSub
1617  * @see u_strFromJavaModifiedUTF8WithSub
1618  */
1619 U_CAPI char* U_EXPORT2
1620 u_strToJavaModifiedUTF8(
1621         char *dest,
1622         int32_t destCapacity,
1623         int32_t *pDestLength,
1624         const UChar *src,
1625         int32_t srcLength,
1626         UErrorCode *pErrorCode);
1627 
1628 /**
1629  * Convert a Java Modified UTF-8 string to a 16-bit Unicode string.
1630  * If the input string is not well-formed and no substitution char is specified,
1631  * then the U_INVALID_CHAR_FOUND error code is set.
1632  *
1633  * This function behaves according to the documentation for Java DataInput.readUTF()
1634  * except that it takes a length parameter rather than
1635  * interpreting the first two input bytes as the length.
1636  * See http://java.sun.com/javase/6/docs/api/java/io/DataInput.html#readUTF()
1637  *
1638  * The output string may not be well-formed UTF-16.
1639  *
1640  * @param dest          A buffer for the result string. The result will be zero-terminated if
1641  *                      the buffer is large enough.
1642  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
1643  *                      dest may be NULL and the function will only return the length of the
1644  *                      result without writing any of the result string (pre-flighting).
1645  * @param pDestLength   A pointer to receive the number of units written to the destination. If
1646  *                      pDestLength!=NULL then *pDestLength is always set to the
1647  *                      number of output units corresponding to the transformation of
1648  *                      all the input units, even in case of a buffer overflow.
1649  * @param src           The original source string
1650  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
1651  * @param subchar       The substitution character to use in place of an illegal input sequence,
1652  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
1653  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
1654  *                      except for surrogate code points (U+D800..U+DFFF).
1655  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
1656  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
1657  *                      Set to 0 if no substitutions occur or subchar<0.
1658  *                      pNumSubstitutions can be NULL.
1659  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
1660  *                      pass the U_SUCCESS() test, or else the function returns
1661  *                      immediately. Check for U_FAILURE() on output or use with
1662  *                      function chaining. (See User Guide for details.)
1663  * @return The pointer to destination buffer.
1664  * @see u_strFromUTF8WithSub
1665  * @see u_strFromUTF8Lenient
1666  * @see u_strToJavaModifiedUTF8
1667  * @stable ICU 4.4
1668  */
1669 U_CAPI UChar* U_EXPORT2
1670 u_strFromJavaModifiedUTF8WithSub(
1671         UChar *dest,
1672         int32_t destCapacity,
1673         int32_t *pDestLength,
1674         const char *src,
1675         int32_t srcLength,
1676         UChar32 subchar, int32_t *pNumSubstitutions,
1677         UErrorCode *pErrorCode);
1678 
1679 #endif
1680