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      1 /*
      2 **********************************************************************
      3 *   Copyright (C) 1998-2010, International Business Machines
      4 *   Corporation and others.  All Rights Reserved.
      5 **********************************************************************
      6 *
      7 * File ustring.h
      8 *
      9 * Modification History:
     10 *
     11 *   Date        Name        Description
     12 *   12/07/98    bertrand    Creation.
     13 ******************************************************************************
     14 */
     15 
     16 #ifndef USTRING_H
     17 #define USTRING_H
     18 
     19 #include "unicode/utypes.h"
     20 #include "unicode/putil.h"
     21 #include "unicode/uiter.h"
     22 
     23 /** Simple declaration for u_strToTitle() to avoid including unicode/ubrk.h. @stable ICU 2.1*/
     24 #ifndef UBRK_TYPEDEF_UBREAK_ITERATOR
     25 #   define UBRK_TYPEDEF_UBREAK_ITERATOR
     26     typedef struct UBreakIterator UBreakIterator;
     27 #endif
     28 
     29 /**
     30  * \file
     31  * \brief C API: Unicode string handling functions
     32  *
     33  * These C API functions provide general Unicode string handling.
     34  *
     35  * Some functions are equivalent in name, signature, and behavior to the ANSI C <string.h>
     36  * functions. (For example, they do not check for bad arguments like NULL string pointers.)
     37  * In some cases, only the thread-safe variant of such a function is implemented here
     38  * (see u_strtok_r()).
     39  *
     40  * Other functions provide more Unicode-specific functionality like locale-specific
     41  * upper/lower-casing and string comparison in code point order.
     42  *
     43  * ICU uses 16-bit Unicode (UTF-16) in the form of arrays of UChar code units.
     44  * UTF-16 encodes each Unicode code point with either one or two UChar code units.
     45  * (This is the default form of Unicode, and a forward-compatible extension of the original,
     46  * fixed-width form that was known as UCS-2. UTF-16 superseded UCS-2 with Unicode 2.0
     47  * in 1996.)
     48  *
     49  * Some APIs accept a 32-bit UChar32 value for a single code point.
     50  *
     51  * ICU also handles 16-bit Unicode text with unpaired surrogates.
     52  * Such text is not well-formed UTF-16.
     53  * Code-point-related functions treat unpaired surrogates as surrogate code points,
     54  * i.e., as separate units.
     55  *
     56  * Although UTF-16 is a variable-width encoding form (like some legacy multi-byte encodings),
     57  * it is much more efficient even for random access because the code unit values
     58  * for single-unit characters vs. lead units vs. trail units are completely disjoint.
     59  * This means that it is easy to determine character (code point) boundaries from
     60  * random offsets in the string.
     61  *
     62  * Unicode (UTF-16) string processing is optimized for the single-unit case.
     63  * Although it is important to support supplementary characters
     64  * (which use pairs of lead/trail code units called "surrogates"),
     65  * their occurrence is rare. Almost all characters in modern use require only
     66  * a single UChar code unit (i.e., their code point values are <=0xffff).
     67  *
     68  * For more details see the User Guide Strings chapter (http://icu-project.org/userguide/strings.html).
     69  * For a discussion of the handling of unpaired surrogates see also
     70  * Jitterbug 2145 and its icu mailing list proposal on 2002-sep-18.
     71  */
     72 
     73 /**
     74  * \defgroup ustring_ustrlen String Length
     75  * \ingroup ustring_strlen
     76  */
     77 /*@{*/
     78 /**
     79  * Determine the length of an array of UChar.
     80  *
     81  * @param s The array of UChars, NULL (U+0000) terminated.
     82  * @return The number of UChars in <code>chars</code>, minus the terminator.
     83  * @stable ICU 2.0
     84  */
     85 U_STABLE int32_t U_EXPORT2
     86 u_strlen(const UChar *s);
     87 /*@}*/
     88 
     89 /**
     90  * Count Unicode code points in the length UChar code units of the string.
     91  * A code point may occupy either one or two UChar code units.
     92  * Counting code points involves reading all code units.
     93  *
     94  * This functions is basically the inverse of the U16_FWD_N() macro (see utf.h).
     95  *
     96  * @param s The input string.
     97  * @param length The number of UChar code units to be checked, or -1 to count all
     98  *               code points before the first NUL (U+0000).
     99  * @return The number of code points in the specified code units.
    100  * @stable ICU 2.0
    101  */
    102 U_STABLE int32_t U_EXPORT2
    103 u_countChar32(const UChar *s, int32_t length);
    104 
    105 /**
    106  * Check if the string contains more Unicode code points than a certain number.
    107  * This is more efficient than counting all code points in the entire string
    108  * and comparing that number with a threshold.
    109  * This function may not need to scan the string at all if the length is known
    110  * (not -1 for NUL-termination) and falls within a certain range, and
    111  * never needs to count more than 'number+1' code points.
    112  * Logically equivalent to (u_countChar32(s, length)>number).
    113  * A Unicode code point may occupy either one or two UChar code units.
    114  *
    115  * @param s The input string.
    116  * @param length The length of the string, or -1 if it is NUL-terminated.
    117  * @param number The number of code points in the string is compared against
    118  *               the 'number' parameter.
    119  * @return Boolean value for whether the string contains more Unicode code points
    120  *         than 'number'. Same as (u_countChar32(s, length)>number).
    121  * @stable ICU 2.4
    122  */
    123 U_STABLE UBool U_EXPORT2
    124 u_strHasMoreChar32Than(const UChar *s, int32_t length, int32_t number);
    125 
    126 /**
    127  * Concatenate two ustrings.  Appends a copy of <code>src</code>,
    128  * including the null terminator, to <code>dst</code>. The initial copied
    129  * character from <code>src</code> overwrites the null terminator in <code>dst</code>.
    130  *
    131  * @param dst The destination string.
    132  * @param src The source string.
    133  * @return A pointer to <code>dst</code>.
    134  * @stable ICU 2.0
    135  */
    136 U_STABLE UChar* U_EXPORT2
    137 u_strcat(UChar     *dst,
    138     const UChar     *src);
    139 
    140 /**
    141  * Concatenate two ustrings.
    142  * Appends at most <code>n</code> characters from <code>src</code> to <code>dst</code>.
    143  * Adds a terminating NUL.
    144  * If src is too long, then only <code>n-1</code> characters will be copied
    145  * before the terminating NUL.
    146  * If <code>n&lt;=0</code> then dst is not modified.
    147  *
    148  * @param dst The destination string.
    149  * @param src The source string.
    150  * @param n The maximum number of characters to append.
    151  * @return A pointer to <code>dst</code>.
    152  * @stable ICU 2.0
    153  */
    154 U_STABLE UChar* U_EXPORT2
    155 u_strncat(UChar     *dst,
    156      const UChar     *src,
    157      int32_t     n);
    158 
    159 /**
    160  * Find the first occurrence of a substring in a string.
    161  * The substring is found at code point boundaries.
    162  * That means that if the substring begins with
    163  * a trail surrogate or ends with a lead surrogate,
    164  * then it is found only if these surrogates stand alone in the text.
    165  * Otherwise, the substring edge units would be matched against
    166  * halves of surrogate pairs.
    167  *
    168  * @param s The string to search (NUL-terminated).
    169  * @param substring The substring to find (NUL-terminated).
    170  * @return A pointer to the first occurrence of <code>substring</code> in <code>s</code>,
    171  *         or <code>s</code> itself if the <code>substring</code> is empty,
    172  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
    173  * @stable ICU 2.0
    174  *
    175  * @see u_strrstr
    176  * @see u_strFindFirst
    177  * @see u_strFindLast
    178  */
    179 U_STABLE UChar * U_EXPORT2
    180 u_strstr(const UChar *s, const UChar *substring);
    181 
    182 /**
    183  * Find the first occurrence of a substring in a string.
    184  * The substring is found at code point boundaries.
    185  * That means that if the substring begins with
    186  * a trail surrogate or ends with a lead surrogate,
    187  * then it is found only if these surrogates stand alone in the text.
    188  * Otherwise, the substring edge units would be matched against
    189  * halves of surrogate pairs.
    190  *
    191  * @param s The string to search.
    192  * @param length The length of s (number of UChars), or -1 if it is NUL-terminated.
    193  * @param substring The substring to find (NUL-terminated).
    194  * @param subLength The length of substring (number of UChars), or -1 if it is NUL-terminated.
    195  * @return A pointer to the first occurrence of <code>substring</code> in <code>s</code>,
    196  *         or <code>s</code> itself if the <code>substring</code> is empty,
    197  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
    198  * @stable ICU 2.4
    199  *
    200  * @see u_strstr
    201  * @see u_strFindLast
    202  */
    203 U_STABLE UChar * U_EXPORT2
    204 u_strFindFirst(const UChar *s, int32_t length, const UChar *substring, int32_t subLength);
    205 
    206 /**
    207  * Find the first occurrence of a BMP code point in a string.
    208  * A surrogate code point is found only if its match in the text is not
    209  * part of a surrogate pair.
    210  * A NUL character is found at the string terminator.
    211  *
    212  * @param s The string to search (NUL-terminated).
    213  * @param c The BMP code point to find.
    214  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
    215  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    216  * @stable ICU 2.0
    217  *
    218  * @see u_strchr32
    219  * @see u_memchr
    220  * @see u_strstr
    221  * @see u_strFindFirst
    222  */
    223 U_STABLE UChar * U_EXPORT2
    224 u_strchr(const UChar *s, UChar c);
    225 
    226 /**
    227  * Find the first occurrence of a code point in a string.
    228  * A surrogate code point is found only if its match in the text is not
    229  * part of a surrogate pair.
    230  * A NUL character is found at the string terminator.
    231  *
    232  * @param s The string to search (NUL-terminated).
    233  * @param c The code point to find.
    234  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
    235  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    236  * @stable ICU 2.0
    237  *
    238  * @see u_strchr
    239  * @see u_memchr32
    240  * @see u_strstr
    241  * @see u_strFindFirst
    242  */
    243 U_STABLE UChar * U_EXPORT2
    244 u_strchr32(const UChar *s, UChar32 c);
    245 
    246 /**
    247  * Find the last occurrence of a substring in a string.
    248  * The substring is found at code point boundaries.
    249  * That means that if the substring begins with
    250  * a trail surrogate or ends with a lead surrogate,
    251  * then it is found only if these surrogates stand alone in the text.
    252  * Otherwise, the substring edge units would be matched against
    253  * halves of surrogate pairs.
    254  *
    255  * @param s The string to search (NUL-terminated).
    256  * @param substring The substring to find (NUL-terminated).
    257  * @return A pointer to the last occurrence of <code>substring</code> in <code>s</code>,
    258  *         or <code>s</code> itself if the <code>substring</code> is empty,
    259  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
    260  * @stable ICU 2.4
    261  *
    262  * @see u_strstr
    263  * @see u_strFindFirst
    264  * @see u_strFindLast
    265  */
    266 U_STABLE UChar * U_EXPORT2
    267 u_strrstr(const UChar *s, const UChar *substring);
    268 
    269 /**
    270  * Find the last occurrence of a substring in a string.
    271  * The substring is found at code point boundaries.
    272  * That means that if the substring begins with
    273  * a trail surrogate or ends with a lead surrogate,
    274  * then it is found only if these surrogates stand alone in the text.
    275  * Otherwise, the substring edge units would be matched against
    276  * halves of surrogate pairs.
    277  *
    278  * @param s The string to search.
    279  * @param length The length of s (number of UChars), or -1 if it is NUL-terminated.
    280  * @param substring The substring to find (NUL-terminated).
    281  * @param subLength The length of substring (number of UChars), or -1 if it is NUL-terminated.
    282  * @return A pointer to the last occurrence of <code>substring</code> in <code>s</code>,
    283  *         or <code>s</code> itself if the <code>substring</code> is empty,
    284  *         or <code>NULL</code> if <code>substring</code> is not in <code>s</code>.
    285  * @stable ICU 2.4
    286  *
    287  * @see u_strstr
    288  * @see u_strFindLast
    289  */
    290 U_STABLE UChar * U_EXPORT2
    291 u_strFindLast(const UChar *s, int32_t length, const UChar *substring, int32_t subLength);
    292 
    293 /**
    294  * Find the last occurrence of a BMP code point in a string.
    295  * A surrogate code point is found only if its match in the text is not
    296  * part of a surrogate pair.
    297  * A NUL character is found at the string terminator.
    298  *
    299  * @param s The string to search (NUL-terminated).
    300  * @param c The BMP code point to find.
    301  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
    302  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    303  * @stable ICU 2.4
    304  *
    305  * @see u_strrchr32
    306  * @see u_memrchr
    307  * @see u_strrstr
    308  * @see u_strFindLast
    309  */
    310 U_STABLE UChar * U_EXPORT2
    311 u_strrchr(const UChar *s, UChar c);
    312 
    313 /**
    314  * Find the last occurrence of a code point in a string.
    315  * A surrogate code point is found only if its match in the text is not
    316  * part of a surrogate pair.
    317  * A NUL character is found at the string terminator.
    318  *
    319  * @param s The string to search (NUL-terminated).
    320  * @param c The code point to find.
    321  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
    322  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    323  * @stable ICU 2.4
    324  *
    325  * @see u_strrchr
    326  * @see u_memchr32
    327  * @see u_strrstr
    328  * @see u_strFindLast
    329  */
    330 U_STABLE UChar * U_EXPORT2
    331 u_strrchr32(const UChar *s, UChar32 c);
    332 
    333 /**
    334  * Locates the first occurrence in the string <code>string</code> of any of the characters
    335  * in the string <code>matchSet</code>.
    336  * Works just like C's strpbrk but with Unicode.
    337  *
    338  * @param string The string in which to search, NUL-terminated.
    339  * @param matchSet A NUL-terminated string defining a set of code points
    340  *                 for which to search in the text string.
    341  * @return A pointer to the  character in <code>string</code> that matches one of the
    342  *         characters in <code>matchSet</code>, or NULL if no such character is found.
    343  * @stable ICU 2.0
    344  */
    345 U_STABLE UChar * U_EXPORT2
    346 u_strpbrk(const UChar *string, const UChar *matchSet);
    347 
    348 /**
    349  * Returns the number of consecutive characters in <code>string</code>,
    350  * beginning with the first, that do not occur somewhere in <code>matchSet</code>.
    351  * Works just like C's strcspn but with Unicode.
    352  *
    353  * @param string The string in which to search, NUL-terminated.
    354  * @param matchSet A NUL-terminated string defining a set of code points
    355  *                 for which to search in the text string.
    356  * @return The number of initial characters in <code>string</code> that do not
    357  *         occur in <code>matchSet</code>.
    358  * @see u_strspn
    359  * @stable ICU 2.0
    360  */
    361 U_STABLE int32_t U_EXPORT2
    362 u_strcspn(const UChar *string, const UChar *matchSet);
    363 
    364 /**
    365  * Returns the number of consecutive characters in <code>string</code>,
    366  * beginning with the first, that occur somewhere in <code>matchSet</code>.
    367  * Works just like C's strspn but with Unicode.
    368  *
    369  * @param string The string in which to search, NUL-terminated.
    370  * @param matchSet A NUL-terminated string defining a set of code points
    371  *                 for which to search in the text string.
    372  * @return The number of initial characters in <code>string</code> that do
    373  *         occur in <code>matchSet</code>.
    374  * @see u_strcspn
    375  * @stable ICU 2.0
    376  */
    377 U_STABLE int32_t U_EXPORT2
    378 u_strspn(const UChar *string, const UChar *matchSet);
    379 
    380 /**
    381  * The string tokenizer API allows an application to break a string into
    382  * tokens. Unlike strtok(), the saveState (the current pointer within the
    383  * original string) is maintained in saveState. In the first call, the
    384  * argument src is a pointer to the string. In subsequent calls to
    385  * return successive tokens of that string, src must be specified as
    386  * NULL. The value saveState is set by this function to maintain the
    387  * function's position within the string, and on each subsequent call
    388  * you must give this argument the same variable. This function does
    389  * handle surrogate pairs. This function is similar to the strtok_r()
    390  * the POSIX Threads Extension (1003.1c-1995) version.
    391  *
    392  * @param src String containing token(s). This string will be modified.
    393  *            After the first call to u_strtok_r(), this argument must
    394  *            be NULL to get to the next token.
    395  * @param delim Set of delimiter characters (Unicode code points).
    396  * @param saveState The current pointer within the original string,
    397  *              which is set by this function. The saveState
    398  *              parameter should the address of a local variable of type
    399  *              UChar *. (i.e. defined "Uhar *myLocalSaveState" and use
    400  *              &myLocalSaveState for this parameter).
    401  * @return A pointer to the next token found in src, or NULL
    402  *         when there are no more tokens.
    403  * @stable ICU 2.0
    404  */
    405 U_STABLE UChar * U_EXPORT2
    406 u_strtok_r(UChar    *src,
    407      const UChar    *delim,
    408            UChar   **saveState);
    409 
    410 /**
    411  * Compare two Unicode strings for bitwise equality (code unit order).
    412  *
    413  * @param s1 A string to compare.
    414  * @param s2 A string to compare.
    415  * @return 0 if <code>s1</code> and <code>s2</code> are bitwise equal; a negative
    416  * value if <code>s1</code> is bitwise less than <code>s2,</code>; a positive
    417  * value if <code>s1</code> is bitwise greater than <code>s2</code>.
    418  * @stable ICU 2.0
    419  */
    420 U_STABLE int32_t  U_EXPORT2
    421 u_strcmp(const UChar     *s1,
    422          const UChar     *s2);
    423 
    424 /**
    425  * Compare two Unicode strings in code point order.
    426  * See u_strCompare for details.
    427  *
    428  * @param s1 A string to compare.
    429  * @param s2 A string to compare.
    430  * @return a negative/zero/positive integer corresponding to whether
    431  * the first string is less than/equal to/greater than the second one
    432  * in code point order
    433  * @stable ICU 2.0
    434  */
    435 U_STABLE int32_t U_EXPORT2
    436 u_strcmpCodePointOrder(const UChar *s1, const UChar *s2);
    437 
    438 /**
    439  * Compare two Unicode strings (binary order).
    440  *
    441  * The comparison can be done in code unit order or in code point order.
    442  * They differ only in UTF-16 when
    443  * comparing supplementary code points (U+10000..U+10ffff)
    444  * to BMP code points near the end of the BMP (i.e., U+e000..U+ffff).
    445  * In code unit order, high BMP code points sort after supplementary code points
    446  * because they are stored as pairs of surrogates which are at U+d800..U+dfff.
    447  *
    448  * This functions works with strings of different explicitly specified lengths
    449  * unlike the ANSI C-like u_strcmp() and u_memcmp() etc.
    450  * NUL-terminated strings are possible with length arguments of -1.
    451  *
    452  * @param s1 First source string.
    453  * @param length1 Length of first source string, or -1 if NUL-terminated.
    454  *
    455  * @param s2 Second source string.
    456  * @param length2 Length of second source string, or -1 if NUL-terminated.
    457  *
    458  * @param codePointOrder Choose between code unit order (FALSE)
    459  *                       and code point order (TRUE).
    460  *
    461  * @return <0 or 0 or >0 as usual for string comparisons
    462  *
    463  * @stable ICU 2.2
    464  */
    465 U_STABLE int32_t U_EXPORT2
    466 u_strCompare(const UChar *s1, int32_t length1,
    467              const UChar *s2, int32_t length2,
    468              UBool codePointOrder);
    469 
    470 /**
    471  * Compare two Unicode strings (binary order)
    472  * as presented by UCharIterator objects.
    473  * Works otherwise just like u_strCompare().
    474  *
    475  * Both iterators are reset to their start positions.
    476  * When the function returns, it is undefined where the iterators
    477  * have stopped.
    478  *
    479  * @param iter1 First source string iterator.
    480  * @param iter2 Second source string iterator.
    481  * @param codePointOrder Choose between code unit order (FALSE)
    482  *                       and code point order (TRUE).
    483  *
    484  * @return <0 or 0 or >0 as usual for string comparisons
    485  *
    486  * @see u_strCompare
    487  *
    488  * @stable ICU 2.6
    489  */
    490 U_STABLE int32_t U_EXPORT2
    491 u_strCompareIter(UCharIterator *iter1, UCharIterator *iter2, UBool codePointOrder);
    492 
    493 #ifndef U_COMPARE_CODE_POINT_ORDER
    494 /* see also unistr.h and unorm.h */
    495 /**
    496  * Option bit for u_strCaseCompare, u_strcasecmp, unorm_compare, etc:
    497  * Compare strings in code point order instead of code unit order.
    498  * @stable ICU 2.2
    499  */
    500 #define U_COMPARE_CODE_POINT_ORDER  0x8000
    501 #endif
    502 
    503 /**
    504  * Compare two strings case-insensitively using full case folding.
    505  * This is equivalent to
    506  *   u_strCompare(u_strFoldCase(s1, options),
    507  *                u_strFoldCase(s2, options),
    508  *                (options&U_COMPARE_CODE_POINT_ORDER)!=0).
    509  *
    510  * The comparison can be done in UTF-16 code unit order or in code point order.
    511  * They differ only when comparing supplementary code points (U+10000..U+10ffff)
    512  * to BMP code points near the end of the BMP (i.e., U+e000..U+ffff).
    513  * In code unit order, high BMP code points sort after supplementary code points
    514  * because they are stored as pairs of surrogates which are at U+d800..U+dfff.
    515  *
    516  * This functions works with strings of different explicitly specified lengths
    517  * unlike the ANSI C-like u_strcmp() and u_memcmp() etc.
    518  * NUL-terminated strings are possible with length arguments of -1.
    519  *
    520  * @param s1 First source string.
    521  * @param length1 Length of first source string, or -1 if NUL-terminated.
    522  *
    523  * @param s2 Second source string.
    524  * @param length2 Length of second source string, or -1 if NUL-terminated.
    525  *
    526  * @param options A bit set of options:
    527  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
    528  *     Comparison in code unit order with default case folding.
    529  *
    530  *   - U_COMPARE_CODE_POINT_ORDER
    531  *     Set to choose code point order instead of code unit order
    532  *     (see u_strCompare for details).
    533  *
    534  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
    535  *
    536  * @param pErrorCode Must be a valid pointer to an error code value,
    537  *                  which must not indicate a failure before the function call.
    538  *
    539  * @return <0 or 0 or >0 as usual for string comparisons
    540  *
    541  * @stable ICU 2.2
    542  */
    543 U_STABLE int32_t U_EXPORT2
    544 u_strCaseCompare(const UChar *s1, int32_t length1,
    545                  const UChar *s2, int32_t length2,
    546                  uint32_t options,
    547                  UErrorCode *pErrorCode);
    548 
    549 /**
    550  * Compare two ustrings for bitwise equality.
    551  * Compares at most <code>n</code> characters.
    552  *
    553  * @param ucs1 A string to compare.
    554  * @param ucs2 A string to compare.
    555  * @param n The maximum number of characters to compare.
    556  * @return 0 if <code>s1</code> and <code>s2</code> are bitwise equal; a negative
    557  * value if <code>s1</code> is bitwise less than <code>s2</code>; a positive
    558  * value if <code>s1</code> is bitwise greater than <code>s2</code>.
    559  * @stable ICU 2.0
    560  */
    561 U_STABLE int32_t U_EXPORT2
    562 u_strncmp(const UChar     *ucs1,
    563      const UChar     *ucs2,
    564      int32_t     n);
    565 
    566 /**
    567  * Compare two Unicode strings in code point order.
    568  * This is different in UTF-16 from u_strncmp() if supplementary characters are present.
    569  * For details, see u_strCompare().
    570  *
    571  * @param s1 A string to compare.
    572  * @param s2 A string to compare.
    573  * @param n The maximum number of characters to compare.
    574  * @return a negative/zero/positive integer corresponding to whether
    575  * the first string is less than/equal to/greater than the second one
    576  * in code point order
    577  * @stable ICU 2.0
    578  */
    579 U_STABLE int32_t U_EXPORT2
    580 u_strncmpCodePointOrder(const UChar *s1, const UChar *s2, int32_t n);
    581 
    582 /**
    583  * Compare two strings case-insensitively using full case folding.
    584  * This is equivalent to u_strcmp(u_strFoldCase(s1, options), u_strFoldCase(s2, options)).
    585  *
    586  * @param s1 A string to compare.
    587  * @param s2 A string to compare.
    588  * @param options A bit set of options:
    589  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
    590  *     Comparison in code unit order with default case folding.
    591  *
    592  *   - U_COMPARE_CODE_POINT_ORDER
    593  *     Set to choose code point order instead of code unit order
    594  *     (see u_strCompare for details).
    595  *
    596  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
    597  *
    598  * @return A negative, zero, or positive integer indicating the comparison result.
    599  * @stable ICU 2.0
    600  */
    601 U_STABLE int32_t U_EXPORT2
    602 u_strcasecmp(const UChar *s1, const UChar *s2, uint32_t options);
    603 
    604 /**
    605  * Compare two strings case-insensitively using full case folding.
    606  * This is equivalent to u_strcmp(u_strFoldCase(s1, at most n, options),
    607  * u_strFoldCase(s2, at most n, options)).
    608  *
    609  * @param s1 A string to compare.
    610  * @param s2 A string to compare.
    611  * @param n The maximum number of characters each string to case-fold and then compare.
    612  * @param options A bit set of options:
    613  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
    614  *     Comparison in code unit order with default case folding.
    615  *
    616  *   - U_COMPARE_CODE_POINT_ORDER
    617  *     Set to choose code point order instead of code unit order
    618  *     (see u_strCompare for details).
    619  *
    620  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
    621  *
    622  * @return A negative, zero, or positive integer indicating the comparison result.
    623  * @stable ICU 2.0
    624  */
    625 U_STABLE int32_t U_EXPORT2
    626 u_strncasecmp(const UChar *s1, const UChar *s2, int32_t n, uint32_t options);
    627 
    628 /**
    629  * Compare two strings case-insensitively using full case folding.
    630  * This is equivalent to u_strcmp(u_strFoldCase(s1, n, options),
    631  * u_strFoldCase(s2, n, options)).
    632  *
    633  * @param s1 A string to compare.
    634  * @param s2 A string to compare.
    635  * @param length The number of characters in each string to case-fold and then compare.
    636  * @param options A bit set of options:
    637  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
    638  *     Comparison in code unit order with default case folding.
    639  *
    640  *   - U_COMPARE_CODE_POINT_ORDER
    641  *     Set to choose code point order instead of code unit order
    642  *     (see u_strCompare for details).
    643  *
    644  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
    645  *
    646  * @return A negative, zero, or positive integer indicating the comparison result.
    647  * @stable ICU 2.0
    648  */
    649 U_STABLE int32_t U_EXPORT2
    650 u_memcasecmp(const UChar *s1, const UChar *s2, int32_t length, uint32_t options);
    651 
    652 /**
    653  * Copy a ustring. Adds a null terminator.
    654  *
    655  * @param dst The destination string.
    656  * @param src The source string.
    657  * @return A pointer to <code>dst</code>.
    658  * @stable ICU 2.0
    659  */
    660 U_STABLE UChar* U_EXPORT2
    661 u_strcpy(UChar     *dst,
    662     const UChar     *src);
    663 
    664 /**
    665  * Copy a ustring.
    666  * Copies at most <code>n</code> characters.  The result will be null terminated
    667  * if the length of <code>src</code> is less than <code>n</code>.
    668  *
    669  * @param dst The destination string.
    670  * @param src The source string.
    671  * @param n The maximum number of characters to copy.
    672  * @return A pointer to <code>dst</code>.
    673  * @stable ICU 2.0
    674  */
    675 U_STABLE UChar* U_EXPORT2
    676 u_strncpy(UChar     *dst,
    677      const UChar     *src,
    678      int32_t     n);
    679 
    680 #if !UCONFIG_NO_CONVERSION
    681 
    682 /**
    683  * Copy a byte string encoded in the default codepage to a ustring.
    684  * Adds a null terminator.
    685  * Performs a host byte to UChar conversion
    686  *
    687  * @param dst The destination string.
    688  * @param src The source string.
    689  * @return A pointer to <code>dst</code>.
    690  * @stable ICU 2.0
    691  */
    692 U_STABLE UChar* U_EXPORT2 u_uastrcpy(UChar *dst,
    693                const char *src );
    694 
    695 /**
    696  * Copy a byte string encoded in the default codepage to a ustring.
    697  * Copies at most <code>n</code> characters.  The result will be null terminated
    698  * if the length of <code>src</code> is less than <code>n</code>.
    699  * Performs a host byte to UChar conversion
    700  *
    701  * @param dst The destination string.
    702  * @param src The source string.
    703  * @param n The maximum number of characters to copy.
    704  * @return A pointer to <code>dst</code>.
    705  * @stable ICU 2.0
    706  */
    707 U_STABLE UChar* U_EXPORT2 u_uastrncpy(UChar *dst,
    708             const char *src,
    709             int32_t n);
    710 
    711 /**
    712  * Copy ustring to a byte string encoded in the default codepage.
    713  * Adds a null terminator.
    714  * Performs a UChar to host byte conversion
    715  *
    716  * @param dst The destination string.
    717  * @param src The source string.
    718  * @return A pointer to <code>dst</code>.
    719  * @stable ICU 2.0
    720  */
    721 U_STABLE char* U_EXPORT2 u_austrcpy(char *dst,
    722             const UChar *src );
    723 
    724 /**
    725  * Copy ustring to a byte string encoded in the default codepage.
    726  * Copies at most <code>n</code> characters.  The result will be null terminated
    727  * if the length of <code>src</code> is less than <code>n</code>.
    728  * Performs a UChar to host byte conversion
    729  *
    730  * @param dst The destination string.
    731  * @param src The source string.
    732  * @param n The maximum number of characters to copy.
    733  * @return A pointer to <code>dst</code>.
    734  * @stable ICU 2.0
    735  */
    736 U_STABLE char* U_EXPORT2 u_austrncpy(char *dst,
    737             const UChar *src,
    738             int32_t n );
    739 
    740 #endif
    741 
    742 /**
    743  * Synonym for memcpy(), but with UChars only.
    744  * @param dest The destination string
    745  * @param src The source string
    746  * @param count The number of characters to copy
    747  * @return A pointer to <code>dest</code>
    748  * @stable ICU 2.0
    749  */
    750 U_STABLE UChar* U_EXPORT2
    751 u_memcpy(UChar *dest, const UChar *src, int32_t count);
    752 
    753 /**
    754  * Synonym for memmove(), but with UChars only.
    755  * @param dest The destination string
    756  * @param src The source string
    757  * @param count The number of characters to move
    758  * @return A pointer to <code>dest</code>
    759  * @stable ICU 2.0
    760  */
    761 U_STABLE UChar* U_EXPORT2
    762 u_memmove(UChar *dest, const UChar *src, int32_t count);
    763 
    764 /**
    765  * Initialize <code>count</code> characters of <code>dest</code> to <code>c</code>.
    766  *
    767  * @param dest The destination string.
    768  * @param c The character to initialize the string.
    769  * @param count The maximum number of characters to set.
    770  * @return A pointer to <code>dest</code>.
    771  * @stable ICU 2.0
    772  */
    773 U_STABLE UChar* U_EXPORT2
    774 u_memset(UChar *dest, UChar c, int32_t count);
    775 
    776 /**
    777  * Compare the first <code>count</code> UChars of each buffer.
    778  *
    779  * @param buf1 The first string to compare.
    780  * @param buf2 The second string to compare.
    781  * @param count The maximum number of UChars to compare.
    782  * @return When buf1 < buf2, a negative number is returned.
    783  *      When buf1 == buf2, 0 is returned.
    784  *      When buf1 > buf2, a positive number is returned.
    785  * @stable ICU 2.0
    786  */
    787 U_STABLE int32_t U_EXPORT2
    788 u_memcmp(const UChar *buf1, const UChar *buf2, int32_t count);
    789 
    790 /**
    791  * Compare two Unicode strings in code point order.
    792  * This is different in UTF-16 from u_memcmp() if supplementary characters are present.
    793  * For details, see u_strCompare().
    794  *
    795  * @param s1 A string to compare.
    796  * @param s2 A string to compare.
    797  * @param count The maximum number of characters to compare.
    798  * @return a negative/zero/positive integer corresponding to whether
    799  * the first string is less than/equal to/greater than the second one
    800  * in code point order
    801  * @stable ICU 2.0
    802  */
    803 U_STABLE int32_t U_EXPORT2
    804 u_memcmpCodePointOrder(const UChar *s1, const UChar *s2, int32_t count);
    805 
    806 /**
    807  * Find the first occurrence of a BMP code point in a string.
    808  * A surrogate code point is found only if its match in the text is not
    809  * part of a surrogate pair.
    810  * A NUL character is found at the string terminator.
    811  *
    812  * @param s The string to search (contains <code>count</code> UChars).
    813  * @param c The BMP code point to find.
    814  * @param count The length of the string.
    815  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
    816  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    817  * @stable ICU 2.0
    818  *
    819  * @see u_strchr
    820  * @see u_memchr32
    821  * @see u_strFindFirst
    822  */
    823 U_STABLE UChar* U_EXPORT2
    824 u_memchr(const UChar *s, UChar c, int32_t count);
    825 
    826 /**
    827  * Find the first occurrence of a code point in a string.
    828  * A surrogate code point is found only if its match in the text is not
    829  * part of a surrogate pair.
    830  * A NUL character is found at the string terminator.
    831  *
    832  * @param s The string to search (contains <code>count</code> UChars).
    833  * @param c The code point to find.
    834  * @param count The length of the string.
    835  * @return A pointer to the first occurrence of <code>c</code> in <code>s</code>
    836  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    837  * @stable ICU 2.0
    838  *
    839  * @see u_strchr32
    840  * @see u_memchr
    841  * @see u_strFindFirst
    842  */
    843 U_STABLE UChar* U_EXPORT2
    844 u_memchr32(const UChar *s, UChar32 c, int32_t count);
    845 
    846 /**
    847  * Find the last occurrence of a BMP code point in a string.
    848  * A surrogate code point is found only if its match in the text is not
    849  * part of a surrogate pair.
    850  * A NUL character is found at the string terminator.
    851  *
    852  * @param s The string to search (contains <code>count</code> UChars).
    853  * @param c The BMP code point to find.
    854  * @param count The length of the string.
    855  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
    856  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    857  * @stable ICU 2.4
    858  *
    859  * @see u_strrchr
    860  * @see u_memrchr32
    861  * @see u_strFindLast
    862  */
    863 U_STABLE UChar* U_EXPORT2
    864 u_memrchr(const UChar *s, UChar c, int32_t count);
    865 
    866 /**
    867  * Find the last occurrence of a code point in a string.
    868  * A surrogate code point is found only if its match in the text is not
    869  * part of a surrogate pair.
    870  * A NUL character is found at the string terminator.
    871  *
    872  * @param s The string to search (contains <code>count</code> UChars).
    873  * @param c The code point to find.
    874  * @param count The length of the string.
    875  * @return A pointer to the last occurrence of <code>c</code> in <code>s</code>
    876  *         or <code>NULL</code> if <code>c</code> is not in <code>s</code>.
    877  * @stable ICU 2.4
    878  *
    879  * @see u_strrchr32
    880  * @see u_memrchr
    881  * @see u_strFindLast
    882  */
    883 U_STABLE UChar* U_EXPORT2
    884 u_memrchr32(const UChar *s, UChar32 c, int32_t count);
    885 
    886 /**
    887  * Unicode String literals in C.
    888  * We need one macro to declare a variable for the string
    889  * and to statically preinitialize it if possible,
    890  * and a second macro to dynamically intialize such a string variable if necessary.
    891  *
    892  * The macros are defined for maximum performance.
    893  * They work only for strings that contain "invariant characters", i.e.,
    894  * only latin letters, digits, and some punctuation.
    895  * See utypes.h for details.
    896  *
    897  * A pair of macros for a single string must be used with the same
    898  * parameters.
    899  * The string parameter must be a C string literal.
    900  * The length of the string, not including the terminating
    901  * <code>NUL</code>, must be specified as a constant.
    902  * The U_STRING_DECL macro should be invoked exactly once for one
    903  * such string variable before it is used.
    904  *
    905  * Usage:
    906  * <pre>
    907  *    U_STRING_DECL(ustringVar1, "Quick-Fox 2", 11);
    908  *    U_STRING_DECL(ustringVar2, "jumps 5%", 8);
    909  *    static UBool didInit=FALSE;
    910  *
    911  *    int32_t function() {
    912  *        if(!didInit) {
    913  *            U_STRING_INIT(ustringVar1, "Quick-Fox 2", 11);
    914  *            U_STRING_INIT(ustringVar2, "jumps 5%", 8);
    915  *            didInit=TRUE;
    916  *        }
    917  *        return u_strcmp(ustringVar1, ustringVar2);
    918  *    }
    919  * </pre>
    920  *
    921  * Note that the macros will NOT consistently work if their argument is another #define.
    922  *  The following will not work on all platforms, don't use it.
    923  *
    924  * <pre>
    925  *     #define GLUCK "Mr. Gluck"
    926  *     U_STRING_DECL(var, GLUCK, 9)
    927  *     U_STRING_INIT(var, GLUCK, 9)
    928  * </pre>
    929  *
    930  * Instead, use the string literal "Mr. Gluck"  as the argument to both macro
    931  * calls.
    932  *
    933  *
    934  * @stable ICU 2.0
    935  */
    936 #if defined(U_DECLARE_UTF16)
    937 #   define U_STRING_DECL(var, cs, length) static const UChar var[(length)+1]=U_DECLARE_UTF16(cs)
    938     /**@stable ICU 2.0 */
    939 #   define U_STRING_INIT(var, cs, length)
    940 #elif U_SIZEOF_WCHAR_T==U_SIZEOF_UCHAR && (U_CHARSET_FAMILY==U_ASCII_FAMILY || (U_SIZEOF_UCHAR == 2 && defined(U_WCHAR_IS_UTF16)))
    941 #   define U_STRING_DECL(var, cs, length) static const UChar var[(length)+1]=L ## cs
    942     /**@stable ICU 2.0 */
    943 #   define U_STRING_INIT(var, cs, length)
    944 #elif U_SIZEOF_UCHAR==1 && U_CHARSET_FAMILY==U_ASCII_FAMILY
    945 #   define U_STRING_DECL(var, cs, length) static const UChar var[(length)+1]=cs
    946     /**@stable ICU 2.0 */
    947 #   define U_STRING_INIT(var, cs, length)
    948 #else
    949 #   define U_STRING_DECL(var, cs, length) static UChar var[(length)+1]
    950     /**@stable ICU 2.0 */
    951 #   define U_STRING_INIT(var, cs, length) u_charsToUChars(cs, var, length+1)
    952 #endif
    953 
    954 /**
    955  * Unescape a string of characters and write the resulting
    956  * Unicode characters to the destination buffer.  The following escape
    957  * sequences are recognized:
    958  *
    959  * \\uhhhh       4 hex digits; h in [0-9A-Fa-f]
    960  * \\Uhhhhhhhh   8 hex digits
    961  * \\xhh         1-2 hex digits
    962  * \\x{h...}     1-8 hex digits
    963  * \\ooo         1-3 octal digits; o in [0-7]
    964  * \\cX          control-X; X is masked with 0x1F
    965  *
    966  * as well as the standard ANSI C escapes:
    967  *
    968  * \\a => U+0007, \\b => U+0008, \\t => U+0009, \\n => U+000A,
    969  * \\v => U+000B, \\f => U+000C, \\r => U+000D, \\e => U+001B,
    970  * \\&quot; => U+0022, \\' => U+0027, \\? => U+003F, \\\\ => U+005C
    971  *
    972  * Anything else following a backslash is generically escaped.  For
    973  * example, "[a\\-z]" returns "[a-z]".
    974  *
    975  * If an escape sequence is ill-formed, this method returns an empty
    976  * string.  An example of an ill-formed sequence is "\\u" followed by
    977  * fewer than 4 hex digits.
    978  *
    979  * The above characters are recognized in the compiler's codepage,
    980  * that is, they are coded as 'u', '\\', etc.  Characters that are
    981  * not parts of escape sequences are converted using u_charsToUChars().
    982  *
    983  * This function is similar to UnicodeString::unescape() but not
    984  * identical to it.  The latter takes a source UnicodeString, so it
    985  * does escape recognition but no conversion.
    986  *
    987  * @param src a zero-terminated string of invariant characters
    988  * @param dest pointer to buffer to receive converted and unescaped
    989  * text and, if there is room, a zero terminator.  May be NULL for
    990  * preflighting, in which case no UChars will be written, but the
    991  * return value will still be valid.  On error, an empty string is
    992  * stored here (if possible).
    993  * @param destCapacity the number of UChars that may be written at
    994  * dest.  Ignored if dest == NULL.
    995  * @return the length of unescaped string.
    996  * @see u_unescapeAt
    997  * @see UnicodeString#unescape()
    998  * @see UnicodeString#unescapeAt()
    999  * @stable ICU 2.0
   1000  */
   1001 U_STABLE int32_t U_EXPORT2
   1002 u_unescape(const char *src,
   1003            UChar *dest, int32_t destCapacity);
   1004 
   1005 U_CDECL_BEGIN
   1006 /**
   1007  * Callback function for u_unescapeAt() that returns a character of
   1008  * the source text given an offset and a context pointer.  The context
   1009  * pointer will be whatever is passed into u_unescapeAt().
   1010  *
   1011  * @param offset pointer to the offset that will be passed to u_unescapeAt().
   1012  * @param context an opaque pointer passed directly into u_unescapeAt()
   1013  * @return the character represented by the escape sequence at
   1014  * offset
   1015  * @see u_unescapeAt
   1016  * @stable ICU 2.0
   1017  */
   1018 typedef UChar (U_CALLCONV *UNESCAPE_CHAR_AT)(int32_t offset, void *context);
   1019 U_CDECL_END
   1020 
   1021 /**
   1022  * Unescape a single sequence. The character at offset-1 is assumed
   1023  * (without checking) to be a backslash.  This method takes a callback
   1024  * pointer to a function that returns the UChar at a given offset.  By
   1025  * varying this callback, ICU functions are able to unescape char*
   1026  * strings, UnicodeString objects, and UFILE pointers.
   1027  *
   1028  * If offset is out of range, or if the escape sequence is ill-formed,
   1029  * (UChar32)0xFFFFFFFF is returned.  See documentation of u_unescape()
   1030  * for a list of recognized sequences.
   1031  *
   1032  * @param charAt callback function that returns a UChar of the source
   1033  * text given an offset and a context pointer.
   1034  * @param offset pointer to the offset that will be passed to charAt.
   1035  * The offset value will be updated upon return to point after the
   1036  * last parsed character of the escape sequence.  On error the offset
   1037  * is unchanged.
   1038  * @param length the number of characters in the source text.  The
   1039  * last character of the source text is considered to be at offset
   1040  * length-1.
   1041  * @param context an opaque pointer passed directly into charAt.
   1042  * @return the character represented by the escape sequence at
   1043  * offset, or (UChar32)0xFFFFFFFF on error.
   1044  * @see u_unescape()
   1045  * @see UnicodeString#unescape()
   1046  * @see UnicodeString#unescapeAt()
   1047  * @stable ICU 2.0
   1048  */
   1049 U_STABLE UChar32 U_EXPORT2
   1050 u_unescapeAt(UNESCAPE_CHAR_AT charAt,
   1051              int32_t *offset,
   1052              int32_t length,
   1053              void *context);
   1054 
   1055 /**
   1056  * Uppercase the characters in a string.
   1057  * Casing is locale-dependent and context-sensitive.
   1058  * The result may be longer or shorter than the original.
   1059  * The source string and the destination buffer are allowed to overlap.
   1060  *
   1061  * @param dest      A buffer for the result string. The result will be zero-terminated if
   1062  *                  the buffer is large enough.
   1063  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
   1064  *                  dest may be NULL and the function will only return the length of the result
   1065  *                  without writing any of the result string.
   1066  * @param src       The original string
   1067  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
   1068  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
   1069  * @param pErrorCode Must be a valid pointer to an error code value,
   1070  *                  which must not indicate a failure before the function call.
   1071  * @return The length of the result string. It may be greater than destCapacity. In that case,
   1072  *         only some of the result was written to the destination buffer.
   1073  * @stable ICU 2.0
   1074  */
   1075 U_STABLE int32_t U_EXPORT2
   1076 u_strToUpper(UChar *dest, int32_t destCapacity,
   1077              const UChar *src, int32_t srcLength,
   1078              const char *locale,
   1079              UErrorCode *pErrorCode);
   1080 
   1081 /**
   1082  * Lowercase the characters in a string.
   1083  * Casing is locale-dependent and context-sensitive.
   1084  * The result may be longer or shorter than the original.
   1085  * The source string and the destination buffer are allowed to overlap.
   1086  *
   1087  * @param dest      A buffer for the result string. The result will be zero-terminated if
   1088  *                  the buffer is large enough.
   1089  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
   1090  *                  dest may be NULL and the function will only return the length of the result
   1091  *                  without writing any of the result string.
   1092  * @param src       The original string
   1093  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
   1094  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
   1095  * @param pErrorCode Must be a valid pointer to an error code value,
   1096  *                  which must not indicate a failure before the function call.
   1097  * @return The length of the result string. It may be greater than destCapacity. In that case,
   1098  *         only some of the result was written to the destination buffer.
   1099  * @stable ICU 2.0
   1100  */
   1101 U_STABLE int32_t U_EXPORT2
   1102 u_strToLower(UChar *dest, int32_t destCapacity,
   1103              const UChar *src, int32_t srcLength,
   1104              const char *locale,
   1105              UErrorCode *pErrorCode);
   1106 
   1107 #if !UCONFIG_NO_BREAK_ITERATION
   1108 
   1109 /**
   1110  * Titlecase a string.
   1111  * Casing is locale-dependent and context-sensitive.
   1112  * Titlecasing uses a break iterator to find the first characters of words
   1113  * that are to be titlecased. It titlecases those characters and lowercases
   1114  * all others.
   1115  *
   1116  * The titlecase break iterator can be provided to customize for arbitrary
   1117  * styles, using rules and dictionaries beyond the standard iterators.
   1118  * It may be more efficient to always provide an iterator to avoid
   1119  * opening and closing one for each string.
   1120  * The standard titlecase iterator for the root locale implements the
   1121  * algorithm of Unicode TR 21.
   1122  *
   1123  * This function uses only the setText(), first() and next() methods of the
   1124  * provided break iterator.
   1125  *
   1126  * The result may be longer or shorter than the original.
   1127  * The source string and the destination buffer are allowed to overlap.
   1128  *
   1129  * @param dest      A buffer for the result string. The result will be zero-terminated if
   1130  *                  the buffer is large enough.
   1131  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
   1132  *                  dest may be NULL and the function will only return the length of the result
   1133  *                  without writing any of the result string.
   1134  * @param src       The original string
   1135  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
   1136  * @param titleIter A break iterator to find the first characters of words
   1137  *                  that are to be titlecased.
   1138  *                  If none is provided (NULL), then a standard titlecase
   1139  *                  break iterator is opened.
   1140  * @param locale    The locale to consider, or "" for the root locale or NULL for the default locale.
   1141  * @param pErrorCode Must be a valid pointer to an error code value,
   1142  *                  which must not indicate a failure before the function call.
   1143  * @return The length of the result string. It may be greater than destCapacity. In that case,
   1144  *         only some of the result was written to the destination buffer.
   1145  * @stable ICU 2.1
   1146  */
   1147 U_STABLE int32_t U_EXPORT2
   1148 u_strToTitle(UChar *dest, int32_t destCapacity,
   1149              const UChar *src, int32_t srcLength,
   1150              UBreakIterator *titleIter,
   1151              const char *locale,
   1152              UErrorCode *pErrorCode);
   1153 
   1154 #endif
   1155 
   1156 /**
   1157  * Case-fold the characters in a string.
   1158  * Case-folding is locale-independent and not context-sensitive,
   1159  * but there is an option for whether to include or exclude mappings for dotted I
   1160  * and dotless i that are marked with 'I' in CaseFolding.txt.
   1161  * The result may be longer or shorter than the original.
   1162  * The source string and the destination buffer are allowed to overlap.
   1163  *
   1164  * @param dest      A buffer for the result string. The result will be zero-terminated if
   1165  *                  the buffer is large enough.
   1166  * @param destCapacity The size of the buffer (number of UChars). If it is 0, then
   1167  *                  dest may be NULL and the function will only return the length of the result
   1168  *                  without writing any of the result string.
   1169  * @param src       The original string
   1170  * @param srcLength The length of the original string. If -1, then src must be zero-terminated.
   1171  * @param options   Either U_FOLD_CASE_DEFAULT or U_FOLD_CASE_EXCLUDE_SPECIAL_I
   1172  * @param pErrorCode Must be a valid pointer to an error code value,
   1173  *                  which must not indicate a failure before the function call.
   1174  * @return The length of the result string. It may be greater than destCapacity. In that case,
   1175  *         only some of the result was written to the destination buffer.
   1176  * @stable ICU 2.0
   1177  */
   1178 U_STABLE int32_t U_EXPORT2
   1179 u_strFoldCase(UChar *dest, int32_t destCapacity,
   1180               const UChar *src, int32_t srcLength,
   1181               uint32_t options,
   1182               UErrorCode *pErrorCode);
   1183 
   1184 #if defined(U_WCHAR_IS_UTF16) || defined(U_WCHAR_IS_UTF32) || !UCONFIG_NO_CONVERSION
   1185 /**
   1186  * Convert a UTF-16 string to a wchar_t string.
   1187  * If it is known at compile time that wchar_t strings are in UTF-16 or UTF-32, then
   1188  * this function simply calls the fast, dedicated function for that.
   1189  * Otherwise, two conversions UTF-16 -> default charset -> wchar_t* are performed.
   1190  *
   1191  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1192  *                      the buffer is large enough.
   1193  * @param destCapacity  The size of the buffer (number of wchar_t's). If it is 0, then
   1194  *                      dest may be NULL and the function will only return the length of the
   1195  *                      result without writing any of the result string (pre-flighting).
   1196  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1197  *                      pDestLength!=NULL then *pDestLength is always set to the
   1198  *                      number of output units corresponding to the transformation of
   1199  *                      all the input units, even in case of a buffer overflow.
   1200  * @param src           The original source string
   1201  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1202  * @param pErrorCode    Must be a valid pointer to an error code value,
   1203  *                      which must not indicate a failure before the function call.
   1204  * @return The pointer to destination buffer.
   1205  * @stable ICU 2.0
   1206  */
   1207 U_STABLE wchar_t* U_EXPORT2
   1208 u_strToWCS(wchar_t *dest,
   1209            int32_t destCapacity,
   1210            int32_t *pDestLength,
   1211            const UChar *src,
   1212            int32_t srcLength,
   1213            UErrorCode *pErrorCode);
   1214 /**
   1215  * Convert a wchar_t string to UTF-16.
   1216  * If it is known at compile time that wchar_t strings are in UTF-16 or UTF-32, then
   1217  * this function simply calls the fast, dedicated function for that.
   1218  * Otherwise, two conversions wchar_t* -> default charset -> UTF-16 are performed.
   1219  *
   1220  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1221  *                      the buffer is large enough.
   1222  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1223  *                      dest may be NULL and the function will only return the length of the
   1224  *                      result without writing any of the result string (pre-flighting).
   1225  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1226  *                      pDestLength!=NULL then *pDestLength is always set to the
   1227  *                      number of output units corresponding to the transformation of
   1228  *                      all the input units, even in case of a buffer overflow.
   1229  * @param src           The original source string
   1230  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1231  * @param pErrorCode    Must be a valid pointer to an error code value,
   1232  *                      which must not indicate a failure before the function call.
   1233  * @return The pointer to destination buffer.
   1234  * @stable ICU 2.0
   1235  */
   1236 U_STABLE UChar* U_EXPORT2
   1237 u_strFromWCS(UChar   *dest,
   1238              int32_t destCapacity,
   1239              int32_t *pDestLength,
   1240              const wchar_t *src,
   1241              int32_t srcLength,
   1242              UErrorCode *pErrorCode);
   1243 #endif /* defined(U_WCHAR_IS_UTF16) || defined(U_WCHAR_IS_UTF32) || !UCONFIG_NO_CONVERSION */
   1244 
   1245 /**
   1246  * Convert a UTF-16 string to UTF-8.
   1247  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1248  *
   1249  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1250  *                      the buffer is large enough.
   1251  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
   1252  *                      dest may be NULL and the function will only return the length of the
   1253  *                      result without writing any of the result string (pre-flighting).
   1254  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1255  *                      pDestLength!=NULL then *pDestLength is always set to the
   1256  *                      number of output units corresponding to the transformation of
   1257  *                      all the input units, even in case of a buffer overflow.
   1258  * @param src           The original source string
   1259  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1260  * @param pErrorCode    Must be a valid pointer to an error code value,
   1261  *                      which must not indicate a failure before the function call.
   1262  * @return The pointer to destination buffer.
   1263  * @stable ICU 2.0
   1264  * @see u_strToUTF8WithSub
   1265  * @see u_strFromUTF8
   1266  */
   1267 U_STABLE char* U_EXPORT2
   1268 u_strToUTF8(char *dest,
   1269             int32_t destCapacity,
   1270             int32_t *pDestLength,
   1271             const UChar *src,
   1272             int32_t srcLength,
   1273             UErrorCode *pErrorCode);
   1274 
   1275 /**
   1276  * Convert a UTF-8 string to UTF-16.
   1277  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1278  *
   1279  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1280  *                      the buffer is large enough.
   1281  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1282  *                      dest may be NULL and the function will only return the length of the
   1283  *                      result without writing any of the result string (pre-flighting).
   1284  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1285  *                      pDestLength!=NULL then *pDestLength is always set to the
   1286  *                      number of output units corresponding to the transformation of
   1287  *                      all the input units, even in case of a buffer overflow.
   1288  * @param src           The original source string
   1289  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1290  * @param pErrorCode    Must be a valid pointer to an error code value,
   1291  *                      which must not indicate a failure before the function call.
   1292  * @return The pointer to destination buffer.
   1293  * @stable ICU 2.0
   1294  * @see u_strFromUTF8WithSub
   1295  * @see u_strFromUTF8Lenient
   1296  */
   1297 U_STABLE UChar* U_EXPORT2
   1298 u_strFromUTF8(UChar *dest,
   1299               int32_t destCapacity,
   1300               int32_t *pDestLength,
   1301               const char *src,
   1302               int32_t srcLength,
   1303               UErrorCode *pErrorCode);
   1304 
   1305 /**
   1306  * Convert a UTF-16 string to UTF-8.
   1307  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1308  *
   1309  * Same as u_strToUTF8() except for the additional subchar which is output for
   1310  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
   1311  * With subchar==U_SENTINEL, this function behaves exactly like u_strToUTF8().
   1312  *
   1313  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1314  *                      the buffer is large enough.
   1315  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
   1316  *                      dest may be NULL and the function will only return the length of the
   1317  *                      result without writing any of the result string (pre-flighting).
   1318  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1319  *                      pDestLength!=NULL then *pDestLength is always set to the
   1320  *                      number of output units corresponding to the transformation of
   1321  *                      all the input units, even in case of a buffer overflow.
   1322  * @param src           The original source string
   1323  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1324  * @param subchar       The substitution character to use in place of an illegal input sequence,
   1325  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
   1326  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
   1327  *                      except for surrogate code points (U+D800..U+DFFF).
   1328  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
   1329  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
   1330  *                      Set to 0 if no substitutions occur or subchar<0.
   1331  *                      pNumSubstitutions can be NULL.
   1332  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1333  *                      pass the U_SUCCESS() test, or else the function returns
   1334  *                      immediately. Check for U_FAILURE() on output or use with
   1335  *                      function chaining. (See User Guide for details.)
   1336  * @return The pointer to destination buffer.
   1337  * @see u_strToUTF8
   1338  * @see u_strFromUTF8WithSub
   1339  * @stable ICU 3.6
   1340  */
   1341 U_STABLE char* U_EXPORT2
   1342 u_strToUTF8WithSub(char *dest,
   1343             int32_t destCapacity,
   1344             int32_t *pDestLength,
   1345             const UChar *src,
   1346             int32_t srcLength,
   1347             UChar32 subchar, int32_t *pNumSubstitutions,
   1348             UErrorCode *pErrorCode);
   1349 
   1350 /**
   1351  * Convert a UTF-8 string to UTF-16.
   1352  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1353  *
   1354  * Same as u_strFromUTF8() except for the additional subchar which is output for
   1355  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
   1356  * With subchar==U_SENTINEL, this function behaves exactly like u_strFromUTF8().
   1357  *
   1358  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1359  *                      the buffer is large enough.
   1360  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1361  *                      dest may be NULL and the function will only return the length of the
   1362  *                      result without writing any of the result string (pre-flighting).
   1363  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1364  *                      pDestLength!=NULL then *pDestLength is always set to the
   1365  *                      number of output units corresponding to the transformation of
   1366  *                      all the input units, even in case of a buffer overflow.
   1367  * @param src           The original source string
   1368  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1369  * @param subchar       The substitution character to use in place of an illegal input sequence,
   1370  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
   1371  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
   1372  *                      except for surrogate code points (U+D800..U+DFFF).
   1373  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
   1374  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
   1375  *                      Set to 0 if no substitutions occur or subchar<0.
   1376  *                      pNumSubstitutions can be NULL.
   1377  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1378  *                      pass the U_SUCCESS() test, or else the function returns
   1379  *                      immediately. Check for U_FAILURE() on output or use with
   1380  *                      function chaining. (See User Guide for details.)
   1381  * @return The pointer to destination buffer.
   1382  * @see u_strFromUTF8
   1383  * @see u_strFromUTF8Lenient
   1384  * @see u_strToUTF8WithSub
   1385  * @stable ICU 3.6
   1386  */
   1387 U_STABLE UChar* U_EXPORT2
   1388 u_strFromUTF8WithSub(UChar *dest,
   1389               int32_t destCapacity,
   1390               int32_t *pDestLength,
   1391               const char *src,
   1392               int32_t srcLength,
   1393               UChar32 subchar, int32_t *pNumSubstitutions,
   1394               UErrorCode *pErrorCode);
   1395 
   1396 /**
   1397  * Convert a UTF-8 string to UTF-16.
   1398  *
   1399  * Same as u_strFromUTF8() except that this function is designed to be very fast,
   1400  * which it achieves by being lenient about malformed UTF-8 sequences.
   1401  * This function is intended for use in environments where UTF-8 text is
   1402  * expected to be well-formed.
   1403  *
   1404  * Its semantics are:
   1405  * - Well-formed UTF-8 text is correctly converted to well-formed UTF-16 text.
   1406  * - The function will not read beyond the input string, nor write beyond
   1407  *   the destCapacity.
   1408  * - Malformed UTF-8 results in "garbage" 16-bit Unicode strings which may not
   1409  *   be well-formed UTF-16.
   1410  *   The function will resynchronize to valid code point boundaries
   1411  *   within a small number of code points after an illegal sequence.
   1412  * - Non-shortest forms are not detected and will result in "spoofing" output.
   1413  *
   1414  * For further performance improvement, if srcLength is given (>=0),
   1415  * then it must be destCapacity>=srcLength.
   1416  *
   1417  * There is no inverse u_strToUTF8Lenient() function because there is practically
   1418  * no performance gain from not checking that a UTF-16 string is well-formed.
   1419  *
   1420  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1421  *                      the buffer is large enough.
   1422  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1423  *                      dest may be NULL and the function will only return the length of the
   1424  *                      result without writing any of the result string (pre-flighting).
   1425  *                      Unlike for other ICU functions, if srcLength>=0 then it
   1426  *                      must be destCapacity>=srcLength.
   1427  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1428  *                      pDestLength!=NULL then *pDestLength is always set to the
   1429  *                      number of output units corresponding to the transformation of
   1430  *                      all the input units, even in case of a buffer overflow.
   1431  *                      Unlike for other ICU functions, if srcLength>=0 but
   1432  *                      destCapacity<srcLength, then *pDestLength will be set to srcLength
   1433  *                      (and U_BUFFER_OVERFLOW_ERROR will be set)
   1434  *                      regardless of the actual result length.
   1435  * @param src           The original source string
   1436  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1437  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1438  *                      pass the U_SUCCESS() test, or else the function returns
   1439  *                      immediately. Check for U_FAILURE() on output or use with
   1440  *                      function chaining. (See User Guide for details.)
   1441  * @return The pointer to destination buffer.
   1442  * @see u_strFromUTF8
   1443  * @see u_strFromUTF8WithSub
   1444  * @see u_strToUTF8WithSub
   1445  * @stable ICU 3.6
   1446  */
   1447 U_STABLE UChar * U_EXPORT2
   1448 u_strFromUTF8Lenient(UChar *dest,
   1449                      int32_t destCapacity,
   1450                      int32_t *pDestLength,
   1451                      const char *src,
   1452                      int32_t srcLength,
   1453                      UErrorCode *pErrorCode);
   1454 
   1455 /**
   1456  * Convert a UTF-16 string to UTF-32.
   1457  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1458  *
   1459  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1460  *                      the buffer is large enough.
   1461  * @param destCapacity  The size of the buffer (number of UChar32s). If it is 0, then
   1462  *                      dest may be NULL and the function will only return the length of the
   1463  *                      result without writing any of the result string (pre-flighting).
   1464  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1465  *                      pDestLength!=NULL then *pDestLength is always set to the
   1466  *                      number of output units corresponding to the transformation of
   1467  *                      all the input units, even in case of a buffer overflow.
   1468  * @param src           The original source string
   1469  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1470  * @param pErrorCode    Must be a valid pointer to an error code value,
   1471  *                      which must not indicate a failure before the function call.
   1472  * @return The pointer to destination buffer.
   1473  * @see u_strToUTF32WithSub
   1474  * @see u_strFromUTF32
   1475  * @stable ICU 2.0
   1476  */
   1477 U_STABLE UChar32* U_EXPORT2
   1478 u_strToUTF32(UChar32 *dest,
   1479              int32_t  destCapacity,
   1480              int32_t  *pDestLength,
   1481              const UChar *src,
   1482              int32_t  srcLength,
   1483              UErrorCode *pErrorCode);
   1484 
   1485 /**
   1486  * Convert a UTF-32 string to UTF-16.
   1487  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1488  *
   1489  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1490  *                      the buffer is large enough.
   1491  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1492  *                      dest may be NULL and the function will only return the length of the
   1493  *                      result without writing any of the result string (pre-flighting).
   1494  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1495  *                      pDestLength!=NULL then *pDestLength is always set to the
   1496  *                      number of output units corresponding to the transformation of
   1497  *                      all the input units, even in case of a buffer overflow.
   1498  * @param src           The original source string
   1499  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1500  * @param pErrorCode    Must be a valid pointer to an error code value,
   1501  *                      which must not indicate a failure before the function call.
   1502  * @return The pointer to destination buffer.
   1503  * @see u_strFromUTF32WithSub
   1504  * @see u_strToUTF32
   1505  * @stable ICU 2.0
   1506  */
   1507 U_STABLE UChar* U_EXPORT2
   1508 u_strFromUTF32(UChar   *dest,
   1509                int32_t destCapacity,
   1510                int32_t *pDestLength,
   1511                const UChar32 *src,
   1512                int32_t srcLength,
   1513                UErrorCode *pErrorCode);
   1514 
   1515 /**
   1516  * Convert a UTF-16 string to UTF-32.
   1517  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1518  *
   1519  * Same as u_strToUTF32() except for the additional subchar which is output for
   1520  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
   1521  * With subchar==U_SENTINEL, this function behaves exactly like u_strToUTF32().
   1522  *
   1523  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1524  *                      the buffer is large enough.
   1525  * @param destCapacity  The size of the buffer (number of UChar32s). If it is 0, then
   1526  *                      dest may be NULL and the function will only return the length of the
   1527  *                      result without writing any of the result string (pre-flighting).
   1528  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1529  *                      pDestLength!=NULL then *pDestLength is always set to the
   1530  *                      number of output units corresponding to the transformation of
   1531  *                      all the input units, even in case of a buffer overflow.
   1532  * @param src           The original source string
   1533  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1534  * @param subchar       The substitution character to use in place of an illegal input sequence,
   1535  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
   1536  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
   1537  *                      except for surrogate code points (U+D800..U+DFFF).
   1538  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
   1539  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
   1540  *                      Set to 0 if no substitutions occur or subchar<0.
   1541  *                      pNumSubstitutions can be NULL.
   1542  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1543  *                      pass the U_SUCCESS() test, or else the function returns
   1544  *                      immediately. Check for U_FAILURE() on output or use with
   1545  *                      function chaining. (See User Guide for details.)
   1546  * @return The pointer to destination buffer.
   1547  * @see u_strToUTF32
   1548  * @see u_strFromUTF32WithSub
   1549  * @stable ICU 4.2
   1550  */
   1551 U_STABLE UChar32* U_EXPORT2
   1552 u_strToUTF32WithSub(UChar32 *dest,
   1553              int32_t destCapacity,
   1554              int32_t *pDestLength,
   1555              const UChar *src,
   1556              int32_t srcLength,
   1557              UChar32 subchar, int32_t *pNumSubstitutions,
   1558              UErrorCode *pErrorCode);
   1559 
   1560 /**
   1561  * Convert a UTF-32 string to UTF-16.
   1562  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1563  *
   1564  * Same as u_strFromUTF32() except for the additional subchar which is output for
   1565  * illegal input sequences, instead of stopping with the U_INVALID_CHAR_FOUND error code.
   1566  * With subchar==U_SENTINEL, this function behaves exactly like u_strFromUTF32().
   1567  *
   1568  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1569  *                      the buffer is large enough.
   1570  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1571  *                      dest may be NULL and the function will only return the length of the
   1572  *                      result without writing any of the result string (pre-flighting).
   1573  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1574  *                      pDestLength!=NULL then *pDestLength is always set to the
   1575  *                      number of output units corresponding to the transformation of
   1576  *                      all the input units, even in case of a buffer overflow.
   1577  * @param src           The original source string
   1578  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1579  * @param subchar       The substitution character to use in place of an illegal input sequence,
   1580  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
   1581  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
   1582  *                      except for surrogate code points (U+D800..U+DFFF).
   1583  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
   1584  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
   1585  *                      Set to 0 if no substitutions occur or subchar<0.
   1586  *                      pNumSubstitutions can be NULL.
   1587  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1588  *                      pass the U_SUCCESS() test, or else the function returns
   1589  *                      immediately. Check for U_FAILURE() on output or use with
   1590  *                      function chaining. (See User Guide for details.)
   1591  * @return The pointer to destination buffer.
   1592  * @see u_strFromUTF32
   1593  * @see u_strToUTF32WithSub
   1594  * @stable ICU 4.2
   1595  */
   1596 U_STABLE UChar* U_EXPORT2
   1597 u_strFromUTF32WithSub(UChar *dest,
   1598                int32_t destCapacity,
   1599                int32_t *pDestLength,
   1600                const UChar32 *src,
   1601                int32_t srcLength,
   1602                UChar32 subchar, int32_t *pNumSubstitutions,
   1603                UErrorCode *pErrorCode);
   1604 
   1605 /**
   1606  * Convert a 16-bit Unicode string to Java Modified UTF-8.
   1607  * See http://java.sun.com/javase/6/docs/api/java/io/DataInput.html#modified-utf-8
   1608  *
   1609  * This function behaves according to the documentation for Java DataOutput.writeUTF()
   1610  * except that it does not encode the output length in the destination buffer
   1611  * and does not have an output length restriction.
   1612  * See http://java.sun.com/javase/6/docs/api/java/io/DataOutput.html#writeUTF(java.lang.String)
   1613  *
   1614  * The input string need not be well-formed UTF-16.
   1615  * (Therefore there is no subchar parameter.)
   1616  *
   1617  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1618  *                      the buffer is large enough.
   1619  * @param destCapacity  The size of the buffer (number of chars). If it is 0, then
   1620  *                      dest may be NULL and the function will only return the length of the
   1621  *                      result without writing any of the result string (pre-flighting).
   1622  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1623  *                      pDestLength!=NULL then *pDestLength is always set to the
   1624  *                      number of output units corresponding to the transformation of
   1625  *                      all the input units, even in case of a buffer overflow.
   1626  * @param src           The original source string
   1627  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1628  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1629  *                      pass the U_SUCCESS() test, or else the function returns
   1630  *                      immediately. Check for U_FAILURE() on output or use with
   1631  *                      function chaining. (See User Guide for details.)
   1632  * @return The pointer to destination buffer.
   1633  * @stable ICU 4.4
   1634  * @see u_strToUTF8WithSub
   1635  * @see u_strFromJavaModifiedUTF8WithSub
   1636  */
   1637 U_STABLE char* U_EXPORT2
   1638 u_strToJavaModifiedUTF8(
   1639         char *dest,
   1640         int32_t destCapacity,
   1641         int32_t *pDestLength,
   1642         const UChar *src,
   1643         int32_t srcLength,
   1644         UErrorCode *pErrorCode);
   1645 
   1646 /**
   1647  * Convert a Java Modified UTF-8 string to a 16-bit Unicode string.
   1648  * If the input string is not well-formed, then the U_INVALID_CHAR_FOUND error code is set.
   1649  *
   1650  * This function behaves according to the documentation for Java DataInput.readUTF()
   1651  * except that it takes a length parameter rather than
   1652  * interpreting the first two input bytes as the length.
   1653  * See http://java.sun.com/javase/6/docs/api/java/io/DataInput.html#readUTF()
   1654  *
   1655  * The output string may not be well-formed UTF-16.
   1656  *
   1657  * @param dest          A buffer for the result string. The result will be zero-terminated if
   1658  *                      the buffer is large enough.
   1659  * @param destCapacity  The size of the buffer (number of UChars). If it is 0, then
   1660  *                      dest may be NULL and the function will only return the length of the
   1661  *                      result without writing any of the result string (pre-flighting).
   1662  * @param pDestLength   A pointer to receive the number of units written to the destination. If
   1663  *                      pDestLength!=NULL then *pDestLength is always set to the
   1664  *                      number of output units corresponding to the transformation of
   1665  *                      all the input units, even in case of a buffer overflow.
   1666  * @param src           The original source string
   1667  * @param srcLength     The length of the original string. If -1, then src must be zero-terminated.
   1668  * @param subchar       The substitution character to use in place of an illegal input sequence,
   1669  *                      or U_SENTINEL if the function is to return with U_INVALID_CHAR_FOUND instead.
   1670  *                      A substitution character can be any valid Unicode code point (up to U+10FFFF)
   1671  *                      except for surrogate code points (U+D800..U+DFFF).
   1672  *                      The recommended value is U+FFFD "REPLACEMENT CHARACTER".
   1673  * @param pNumSubstitutions Output parameter receiving the number of substitutions if subchar>=0.
   1674  *                      Set to 0 if no substitutions occur or subchar<0.
   1675  *                      pNumSubstitutions can be NULL.
   1676  * @param pErrorCode    Pointer to a standard ICU error code. Its input value must
   1677  *                      pass the U_SUCCESS() test, or else the function returns
   1678  *                      immediately. Check for U_FAILURE() on output or use with
   1679  *                      function chaining. (See User Guide for details.)
   1680  * @return The pointer to destination buffer.
   1681  * @see u_strFromUTF8WithSub
   1682  * @see u_strFromUTF8Lenient
   1683  * @see u_strToJavaModifiedUTF8
   1684  * @stable ICU 4.4
   1685  */
   1686 U_STABLE UChar* U_EXPORT2
   1687 u_strFromJavaModifiedUTF8WithSub(
   1688         UChar *dest,
   1689         int32_t destCapacity,
   1690         int32_t *pDestLength,
   1691         const char *src,
   1692         int32_t srcLength,
   1693         UChar32 subchar, int32_t *pNumSubstitutions,
   1694         UErrorCode *pErrorCode);
   1695 
   1696 #endif
   1697