Home | History | Annotate | Download | only in unicode
      1 /*
      2 **********************************************************************
      3 *   Copyright (C) 1999-2014, International Business Machines
      4 *   Corporation and others.  All Rights Reserved.
      5 **********************************************************************
      6  *  ucnv.h:
      7  *  External APIs for the ICU's codeset conversion library
      8  *  Bertrand A. Damiba
      9  *
     10  * Modification History:
     11  *
     12  *   Date        Name        Description
     13  *   04/04/99    helena      Fixed internal header inclusion.
     14  *   05/11/00    helena      Added setFallback and usesFallback APIs.
     15  *   06/29/2000  helena      Major rewrite of the callback APIs.
     16  *   12/07/2000  srl         Update of documentation
     17  */
     18 
     19 /**
     20  * \file
     21  * \brief C API: Character conversion
     22  *
     23  * <h2>Character Conversion C API</h2>
     24  *
     25  * <p>This API is used to convert codepage or character encoded data to and
     26  * from UTF-16. You can open a converter with {@link ucnv_open() }. With that
     27  * converter, you can get its properties, set options, convert your data and
     28  * close the converter.</p>
     29  *
     30  * <p>Since many software programs recogize different converter names for
     31  * different types of converters, there are other functions in this API to
     32  * iterate over the converter aliases. The functions {@link ucnv_getAvailableName() },
     33  * {@link ucnv_getAlias() } and {@link ucnv_getStandardName() } are some of the
     34  * more frequently used alias functions to get this information.</p>
     35  *
     36  * <p>When a converter encounters an illegal, irregular, invalid or unmappable character
     37  * its default behavior is to use a substitution character to replace the
     38  * bad byte sequence. This behavior can be changed by using {@link ucnv_setFromUCallBack() }
     39  * or {@link ucnv_setToUCallBack() } on the converter. The header ucnv_err.h defines
     40  * many other callback actions that can be used instead of a character substitution.</p>
     41  *
     42  * <p>More information about this API can be found in our
     43  * <a href="http://icu-project.org/userguide/conversion.html">User's
     44  * Guide</a>.</p>
     45  */
     46 
     47 #ifndef UCNV_H
     48 #define UCNV_H
     49 
     50 #include "unicode/ucnv_err.h"
     51 #include "unicode/uenum.h"
     52 #include "unicode/localpointer.h"
     53 
     54 #ifndef __USET_H__
     55 
     56 /**
     57  * USet is the C API type for Unicode sets.
     58  * It is forward-declared here to avoid including the header file if related
     59  * conversion APIs are not used.
     60  * See unicode/uset.h
     61  *
     62  * @see ucnv_getUnicodeSet
     63  * @stable ICU 2.6
     64  */
     65 struct USet;
     66 /** @stable ICU 2.6 */
     67 typedef struct USet USet;
     68 
     69 #endif
     70 
     71 #if !UCONFIG_NO_CONVERSION
     72 
     73 U_CDECL_BEGIN
     74 
     75 /** Maximum length of a converter name including the terminating NULL @stable ICU 2.0 */
     76 #define UCNV_MAX_CONVERTER_NAME_LENGTH 60
     77 /** Maximum length of a converter name including path and terminating NULL @stable ICU 2.0 */
     78 #define UCNV_MAX_FULL_FILE_NAME_LENGTH (600+UCNV_MAX_CONVERTER_NAME_LENGTH)
     79 
     80 /** Shift in for EBDCDIC_STATEFUL and iso2022 states @stable ICU 2.0 */
     81 #define  UCNV_SI 0x0F
     82 /** Shift out for EBDCDIC_STATEFUL and iso2022 states @stable ICU 2.0 */
     83 #define  UCNV_SO 0x0E
     84 
     85 /**
     86  * Enum for specifying basic types of converters
     87  * @see ucnv_getType
     88  * @stable ICU 2.0
     89  */
     90 typedef enum {
     91     /** @stable ICU 2.0 */
     92     UCNV_UNSUPPORTED_CONVERTER = -1,
     93     /** @stable ICU 2.0 */
     94     UCNV_SBCS = 0,
     95     /** @stable ICU 2.0 */
     96     UCNV_DBCS = 1,
     97     /** @stable ICU 2.0 */
     98     UCNV_MBCS = 2,
     99     /** @stable ICU 2.0 */
    100     UCNV_LATIN_1 = 3,
    101     /** @stable ICU 2.0 */
    102     UCNV_UTF8 = 4,
    103     /** @stable ICU 2.0 */
    104     UCNV_UTF16_BigEndian = 5,
    105     /** @stable ICU 2.0 */
    106     UCNV_UTF16_LittleEndian = 6,
    107     /** @stable ICU 2.0 */
    108     UCNV_UTF32_BigEndian = 7,
    109     /** @stable ICU 2.0 */
    110     UCNV_UTF32_LittleEndian = 8,
    111     /** @stable ICU 2.0 */
    112     UCNV_EBCDIC_STATEFUL = 9,
    113     /** @stable ICU 2.0 */
    114     UCNV_ISO_2022 = 10,
    115 
    116     /** @stable ICU 2.0 */
    117     UCNV_LMBCS_1 = 11,
    118     /** @stable ICU 2.0 */
    119     UCNV_LMBCS_2,
    120     /** @stable ICU 2.0 */
    121     UCNV_LMBCS_3,
    122     /** @stable ICU 2.0 */
    123     UCNV_LMBCS_4,
    124     /** @stable ICU 2.0 */
    125     UCNV_LMBCS_5,
    126     /** @stable ICU 2.0 */
    127     UCNV_LMBCS_6,
    128     /** @stable ICU 2.0 */
    129     UCNV_LMBCS_8,
    130     /** @stable ICU 2.0 */
    131     UCNV_LMBCS_11,
    132     /** @stable ICU 2.0 */
    133     UCNV_LMBCS_16,
    134     /** @stable ICU 2.0 */
    135     UCNV_LMBCS_17,
    136     /** @stable ICU 2.0 */
    137     UCNV_LMBCS_18,
    138     /** @stable ICU 2.0 */
    139     UCNV_LMBCS_19,
    140     /** @stable ICU 2.0 */
    141     UCNV_LMBCS_LAST = UCNV_LMBCS_19,
    142     /** @stable ICU 2.0 */
    143     UCNV_HZ,
    144     /** @stable ICU 2.0 */
    145     UCNV_SCSU,
    146     /** @stable ICU 2.0 */
    147     UCNV_ISCII,
    148     /** @stable ICU 2.0 */
    149     UCNV_US_ASCII,
    150     /** @stable ICU 2.0 */
    151     UCNV_UTF7,
    152     /** @stable ICU 2.2 */
    153     UCNV_BOCU1,
    154     /** @stable ICU 2.2 */
    155     UCNV_UTF16,
    156     /** @stable ICU 2.2 */
    157     UCNV_UTF32,
    158     /** @stable ICU 2.2 */
    159     UCNV_CESU8,
    160     /** @stable ICU 2.4 */
    161     UCNV_IMAP_MAILBOX,
    162     /** @stable ICU 4.8 */
    163     UCNV_COMPOUND_TEXT,
    164 
    165     /* Number of converter types for which we have conversion routines. */
    166     UCNV_NUMBER_OF_SUPPORTED_CONVERTER_TYPES
    167 } UConverterType;
    168 
    169 /**
    170  * Enum for specifying which platform a converter ID refers to.
    171  * The use of platform/CCSID is not recommended. See ucnv_openCCSID().
    172  *
    173  * @see ucnv_getPlatform
    174  * @see ucnv_openCCSID
    175  * @see ucnv_getCCSID
    176  * @stable ICU 2.0
    177  */
    178 typedef enum {
    179     UCNV_UNKNOWN = -1,
    180     UCNV_IBM = 0
    181 } UConverterPlatform;
    182 
    183 /**
    184  * Function pointer for error callback in the codepage to unicode direction.
    185  * Called when an error has occured in conversion to unicode, or on open/close of the callback (see reason).
    186  * @param context Pointer to the callback's private data
    187  * @param args Information about the conversion in progress
    188  * @param codeUnits Points to 'length' bytes of the concerned codepage sequence
    189  * @param length Size (in bytes) of the concerned codepage sequence
    190  * @param reason Defines the reason the callback was invoked
    191  * @param pErrorCode    ICU error code in/out parameter.
    192  *                      For converter callback functions, set to a conversion error
    193  *                      before the call, and the callback may reset it to U_ZERO_ERROR.
    194  * @see ucnv_setToUCallBack
    195  * @see UConverterToUnicodeArgs
    196  * @stable ICU 2.0
    197  */
    198 typedef void (U_EXPORT2 *UConverterToUCallback) (
    199                   const void* context,
    200                   UConverterToUnicodeArgs *args,
    201                   const char *codeUnits,
    202                   int32_t length,
    203                   UConverterCallbackReason reason,
    204                   UErrorCode *pErrorCode);
    205 
    206 /**
    207  * Function pointer for error callback in the unicode to codepage direction.
    208  * Called when an error has occured in conversion from unicode, or on open/close of the callback (see reason).
    209  * @param context Pointer to the callback's private data
    210  * @param args Information about the conversion in progress
    211  * @param codeUnits Points to 'length' UChars of the concerned Unicode sequence
    212  * @param length Size (in bytes) of the concerned codepage sequence
    213  * @param codePoint Single UChar32 (UTF-32) containing the concerend Unicode codepoint.
    214  * @param reason Defines the reason the callback was invoked
    215  * @param pErrorCode    ICU error code in/out parameter.
    216  *                      For converter callback functions, set to a conversion error
    217  *                      before the call, and the callback may reset it to U_ZERO_ERROR.
    218  * @see ucnv_setFromUCallBack
    219  * @stable ICU 2.0
    220  */
    221 typedef void (U_EXPORT2 *UConverterFromUCallback) (
    222                     const void* context,
    223                     UConverterFromUnicodeArgs *args,
    224                     const UChar* codeUnits,
    225                     int32_t length,
    226                     UChar32 codePoint,
    227                     UConverterCallbackReason reason,
    228                     UErrorCode *pErrorCode);
    229 
    230 U_CDECL_END
    231 
    232 /**
    233  * Character that separates converter names from options and options from each other.
    234  * @see ucnv_open
    235  * @stable ICU 2.0
    236  */
    237 #define UCNV_OPTION_SEP_CHAR ','
    238 
    239 /**
    240  * String version of UCNV_OPTION_SEP_CHAR.
    241  * @see ucnv_open
    242  * @stable ICU 2.0
    243  */
    244 #define UCNV_OPTION_SEP_STRING ","
    245 
    246 /**
    247  * Character that separates a converter option from its value.
    248  * @see ucnv_open
    249  * @stable ICU 2.0
    250  */
    251 #define UCNV_VALUE_SEP_CHAR '='
    252 
    253 /**
    254  * String version of UCNV_VALUE_SEP_CHAR.
    255  * @see ucnv_open
    256  * @stable ICU 2.0
    257  */
    258 #define UCNV_VALUE_SEP_STRING "="
    259 
    260 /**
    261  * Converter option for specifying a locale.
    262  * For example, ucnv_open("SCSU,locale=ja", &errorCode);
    263  * See convrtrs.txt.
    264  *
    265  * @see ucnv_open
    266  * @stable ICU 2.0
    267  */
    268 #define UCNV_LOCALE_OPTION_STRING ",locale="
    269 
    270 /**
    271  * Converter option for specifying a version selector (0..9) for some converters.
    272  * For example,
    273  * \code
    274  *   ucnv_open("UTF-7,version=1", &errorCode);
    275  * \endcode
    276  * See convrtrs.txt.
    277  *
    278  * @see ucnv_open
    279  * @stable ICU 2.4
    280  */
    281 #define UCNV_VERSION_OPTION_STRING ",version="
    282 
    283 /**
    284  * Converter option for EBCDIC SBCS or mixed-SBCS/DBCS (stateful) codepages.
    285  * Swaps Unicode mappings for EBCDIC LF and NL codes, as used on
    286  * S/390 (z/OS) Unix System Services (Open Edition).
    287  * For example, ucnv_open("ibm-1047,swaplfnl", &errorCode);
    288  * See convrtrs.txt.
    289  *
    290  * @see ucnv_open
    291  * @stable ICU 2.4
    292  */
    293 #define UCNV_SWAP_LFNL_OPTION_STRING ",swaplfnl"
    294 
    295 /**
    296  * Do a fuzzy compare of two converter/alias names.
    297  * The comparison is case-insensitive, ignores leading zeroes if they are not
    298  * followed by further digits, and ignores all but letters and digits.
    299  * Thus the strings "UTF-8", "utf_8", "u*T@f08" and "Utf 8" are exactly equivalent.
    300  * See section 1.4, Charset Alias Matching in Unicode Technical Standard #22
    301  * at http://www.unicode.org/reports/tr22/
    302  *
    303  * @param name1 a converter name or alias, zero-terminated
    304  * @param name2 a converter name or alias, zero-terminated
    305  * @return 0 if the names match, or a negative value if the name1
    306  * lexically precedes name2, or a positive value if the name1
    307  * lexically follows name2.
    308  * @stable ICU 2.0
    309  */
    310 U_STABLE int U_EXPORT2
    311 ucnv_compareNames(const char *name1, const char *name2);
    312 
    313 
    314 /**
    315  * Creates a UConverter object with the name of a coded character set specified as a C string.
    316  * The actual name will be resolved with the alias file
    317  * using a case-insensitive string comparison that ignores
    318  * leading zeroes and all non-alphanumeric characters.
    319  * E.g., the names "UTF8", "utf-8", "u*T@f08" and "Utf 8" are all equivalent.
    320  * (See also ucnv_compareNames().)
    321  * If <code>NULL</code> is passed for the converter name, it will create one with the
    322  * getDefaultName return value.
    323  *
    324  * <p>A converter name for ICU 1.5 and above may contain options
    325  * like a locale specification to control the specific behavior of
    326  * the newly instantiated converter.
    327  * The meaning of the options depends on the particular converter.
    328  * If an option is not defined for or recognized by a given converter, then it is ignored.</p>
    329  *
    330  * <p>Options are appended to the converter name string, with a
    331  * <code>UCNV_OPTION_SEP_CHAR</code> between the name and the first option and
    332  * also between adjacent options.</p>
    333  *
    334  * <p>If the alias is ambiguous, then the preferred converter is used
    335  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.</p>
    336  *
    337  * <p>The conversion behavior and names can vary between platforms. ICU may
    338  * convert some characters differently from other platforms. Details on this topic
    339  * are in the <a href="http://icu-project.org/userguide/conversion.html">User's
    340  * Guide</a>. Aliases starting with a "cp" prefix have no specific meaning
    341  * other than its an alias starting with the letters "cp". Please do not
    342  * associate any meaning to these aliases.</p>
    343  *
    344  * \snippet samples/ucnv/convsamp.cpp ucnv_open
    345  *
    346  * @param converterName Name of the coded character set table.
    347  *          This may have options appended to the string.
    348  *          IANA alias character set names, IBM CCSIDs starting with "ibm-",
    349  *          Windows codepage numbers starting with "windows-" are frequently
    350  *          used for this parameter. See ucnv_getAvailableName and
    351  *          ucnv_getAlias for a complete list that is available.
    352  *          If this parameter is NULL, the default converter will be used.
    353  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>
    354  * @return the created Unicode converter object, or <TT>NULL</TT> if an error occured
    355  * @see ucnv_openU
    356  * @see ucnv_openCCSID
    357  * @see ucnv_getAvailableName
    358  * @see ucnv_getAlias
    359  * @see ucnv_getDefaultName
    360  * @see ucnv_close
    361  * @see ucnv_compareNames
    362  * @stable ICU 2.0
    363  */
    364 U_STABLE UConverter* U_EXPORT2
    365 ucnv_open(const char *converterName, UErrorCode *err);
    366 
    367 
    368 /**
    369  * Creates a Unicode converter with the names specified as unicode string.
    370  * The name should be limited to the ASCII-7 alphanumerics range.
    371  * The actual name will be resolved with the alias file
    372  * using a case-insensitive string comparison that ignores
    373  * leading zeroes and all non-alphanumeric characters.
    374  * E.g., the names "UTF8", "utf-8", "u*T@f08" and "Utf 8" are all equivalent.
    375  * (See also ucnv_compareNames().)
    376  * If <TT>NULL</TT> is passed for the converter name, it will create
    377  * one with the ucnv_getDefaultName() return value.
    378  * If the alias is ambiguous, then the preferred converter is used
    379  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.
    380  *
    381  * <p>See ucnv_open for the complete details</p>
    382  * @param name Name of the UConverter table in a zero terminated
    383  *        Unicode string
    384  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR,
    385  *        U_FILE_ACCESS_ERROR</TT>
    386  * @return the created Unicode converter object, or <TT>NULL</TT> if an
    387  *        error occured
    388  * @see ucnv_open
    389  * @see ucnv_openCCSID
    390  * @see ucnv_close
    391  * @see ucnv_compareNames
    392  * @stable ICU 2.0
    393  */
    394 U_STABLE UConverter* U_EXPORT2
    395 ucnv_openU(const UChar *name,
    396            UErrorCode *err);
    397 
    398 /**
    399  * Creates a UConverter object from a CCSID number and platform pair.
    400  * Note that the usefulness of this function is limited to platforms with numeric
    401  * encoding IDs. Only IBM and Microsoft platforms use numeric (16-bit) identifiers for
    402  * encodings.
    403  *
    404  * In addition, IBM CCSIDs and Unicode conversion tables are not 1:1 related.
    405  * For many IBM CCSIDs there are multiple (up to six) Unicode conversion tables, and
    406  * for some Unicode conversion tables there are multiple CCSIDs.
    407  * Some "alternate" Unicode conversion tables are provided by the
    408  * IBM CDRA conversion table registry.
    409  * The most prominent example of a systematic modification of conversion tables that is
    410  * not provided in the form of conversion table files in the repository is
    411  * that S/390 Unix System Services swaps the codes for Line Feed and New Line in all
    412  * EBCDIC codepages, which requires such a swap in the Unicode conversion tables as well.
    413  *
    414  * Only IBM default conversion tables are accessible with ucnv_openCCSID().
    415  * ucnv_getCCSID() will return the same CCSID for all conversion tables that are associated
    416  * with that CCSID.
    417  *
    418  * Currently, the only "platform" supported in the ICU converter API is UCNV_IBM.
    419  *
    420  * In summary, the use of CCSIDs and the associated API functions is not recommended.
    421  *
    422  * In order to open a converter with the default IBM CDRA Unicode conversion table,
    423  * you can use this function or use the prefix "ibm-":
    424  * \code
    425  *     char name[20];
    426  *     sprintf(name, "ibm-%hu", ccsid);
    427  *     cnv=ucnv_open(name, &errorCode);
    428  * \endcode
    429  *
    430  * In order to open a converter with the IBM S/390 Unix System Services variant
    431  * of a Unicode/EBCDIC conversion table,
    432  * you can use the prefix "ibm-" together with the option string UCNV_SWAP_LFNL_OPTION_STRING:
    433  * \code
    434  *     char name[20];
    435  *     sprintf(name, "ibm-%hu" UCNV_SWAP_LFNL_OPTION_STRING, ccsid);
    436  *     cnv=ucnv_open(name, &errorCode);
    437  * \endcode
    438  *
    439  * In order to open a converter from a Microsoft codepage number, use the prefix "cp":
    440  * \code
    441  *     char name[20];
    442  *     sprintf(name, "cp%hu", codepageID);
    443  *     cnv=ucnv_open(name, &errorCode);
    444  * \endcode
    445  *
    446  * If the alias is ambiguous, then the preferred converter is used
    447  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.
    448  *
    449  * @param codepage codepage number to create
    450  * @param platform the platform in which the codepage number exists
    451  * @param err error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>
    452  * @return the created Unicode converter object, or <TT>NULL</TT> if an error
    453  *   occured.
    454  * @see ucnv_open
    455  * @see ucnv_openU
    456  * @see ucnv_close
    457  * @see ucnv_getCCSID
    458  * @see ucnv_getPlatform
    459  * @see UConverterPlatform
    460  * @stable ICU 2.0
    461  */
    462 U_STABLE UConverter* U_EXPORT2
    463 ucnv_openCCSID(int32_t codepage,
    464                UConverterPlatform platform,
    465                UErrorCode * err);
    466 
    467 /**
    468  * <p>Creates a UConverter object specified from a packageName and a converterName.</p>
    469  *
    470  * <p>The packageName and converterName must point to an ICU udata object, as defined by
    471  *   <code> udata_open( packageName, "cnv", converterName, err) </code> or equivalent.
    472  * Typically, packageName will refer to a (.dat) file, or to a package registered with
    473  * udata_setAppData(). Using a full file or directory pathname for packageName is deprecated.</p>
    474  *
    475  * <p>The name will NOT be looked up in the alias mechanism, nor will the converter be
    476  * stored in the converter cache or the alias table. The only way to open further converters
    477  * is call this function multiple times, or use the ucnv_safeClone() function to clone a
    478  * 'master' converter.</p>
    479  *
    480  * <p>A future version of ICU may add alias table lookups and/or caching
    481  * to this function.</p>
    482  *
    483  * <p>Example Use:
    484  *      <code>cnv = ucnv_openPackage("myapp", "myconverter", &err);</code>
    485  * </p>
    486  *
    487  * @param packageName name of the package (equivalent to 'path' in udata_open() call)
    488  * @param converterName name of the data item to be used, without suffix.
    489  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>
    490  * @return the created Unicode converter object, or <TT>NULL</TT> if an error occured
    491  * @see udata_open
    492  * @see ucnv_open
    493  * @see ucnv_safeClone
    494  * @see ucnv_close
    495  * @stable ICU 2.2
    496  */
    497 U_STABLE UConverter* U_EXPORT2
    498 ucnv_openPackage(const char *packageName, const char *converterName, UErrorCode *err);
    499 
    500 /**
    501  * Thread safe converter cloning operation.
    502  * For most efficient operation, pass in a stackBuffer (and a *pBufferSize)
    503  * with at least U_CNV_SAFECLONE_BUFFERSIZE bytes of space.
    504  * If the buffer size is sufficient, then the clone will use the stack buffer;
    505  * otherwise, it will be allocated, and *pBufferSize will indicate
    506  * the actual size. (This should not occur with U_CNV_SAFECLONE_BUFFERSIZE.)
    507  *
    508  * You must ucnv_close() the clone in any case.
    509  *
    510  * If *pBufferSize==0, (regardless of whether stackBuffer==NULL or not)
    511  * then *pBufferSize will be changed to a sufficient size
    512  * for cloning this converter,
    513  * without actually cloning the converter ("pure pre-flighting").
    514  *
    515  * If *pBufferSize is greater than zero but not large enough for a stack-based
    516  * clone, then the converter is cloned using newly allocated memory
    517  * and *pBufferSize is changed to the necessary size.
    518  *
    519  * If the converter clone fits into the stack buffer but the stack buffer is not
    520  * sufficiently aligned for the clone, then the clone will use an
    521  * adjusted pointer and use an accordingly smaller buffer size.
    522  *
    523  * @param cnv converter to be cloned
    524  * @param stackBuffer <em>Deprecated functionality as of ICU 52, use NULL.</em><br>
    525  *  user allocated space for the new clone. If NULL new memory will be allocated.
    526  *  If buffer is not large enough, new memory will be allocated.
    527  *  Clients can use the U_CNV_SAFECLONE_BUFFERSIZE. This will probably be enough to avoid memory allocations.
    528  * @param pBufferSize <em>Deprecated functionality as of ICU 52, use NULL or 1.</em><br>
    529  *  pointer to size of allocated space.
    530  * @param status to indicate whether the operation went on smoothly or there were errors
    531  *  An informational status value, U_SAFECLONE_ALLOCATED_WARNING,
    532  *  is used if any allocations were necessary.
    533  *  However, it is better to check if *pBufferSize grew for checking for
    534  *  allocations because warning codes can be overridden by subsequent
    535  *  function calls.
    536  * @return pointer to the new clone
    537  * @stable ICU 2.0
    538  */
    539 U_STABLE UConverter * U_EXPORT2
    540 ucnv_safeClone(const UConverter *cnv,
    541                void             *stackBuffer,
    542                int32_t          *pBufferSize,
    543                UErrorCode       *status);
    544 
    545 #ifndef U_HIDE_DEPRECATED_API
    546 
    547 /**
    548  * \def U_CNV_SAFECLONE_BUFFERSIZE
    549  * Definition of a buffer size that is designed to be large enough for
    550  * converters to be cloned with ucnv_safeClone().
    551  * @deprecated ICU 52. Do not rely on ucnv_safeClone() cloning into any provided buffer.
    552  */
    553 #define U_CNV_SAFECLONE_BUFFERSIZE  1024
    554 
    555 #endif /* U_HIDE_DEPRECATED_API */
    556 
    557 /**
    558  * Deletes the unicode converter and releases resources associated
    559  * with just this instance.
    560  * Does not free up shared converter tables.
    561  *
    562  * @param converter the converter object to be deleted
    563  * @see ucnv_open
    564  * @see ucnv_openU
    565  * @see ucnv_openCCSID
    566  * @stable ICU 2.0
    567  */
    568 U_STABLE void  U_EXPORT2
    569 ucnv_close(UConverter * converter);
    570 
    571 #if U_SHOW_CPLUSPLUS_API
    572 
    573 U_NAMESPACE_BEGIN
    574 
    575 /**
    576  * \class LocalUConverterPointer
    577  * "Smart pointer" class, closes a UConverter via ucnv_close().
    578  * For most methods see the LocalPointerBase base class.
    579  *
    580  * @see LocalPointerBase
    581  * @see LocalPointer
    582  * @stable ICU 4.4
    583  */
    584 U_DEFINE_LOCAL_OPEN_POINTER(LocalUConverterPointer, UConverter, ucnv_close);
    585 
    586 U_NAMESPACE_END
    587 
    588 #endif
    589 
    590 /**
    591  * Fills in the output parameter, subChars, with the substitution characters
    592  * as multiple bytes.
    593  * If ucnv_setSubstString() set a Unicode string because the converter is
    594  * stateful, then subChars will be an empty string.
    595  *
    596  * @param converter the Unicode converter
    597  * @param subChars the subsitution characters
    598  * @param len on input the capacity of subChars, on output the number
    599  * of bytes copied to it
    600  * @param  err the outgoing error status code.
    601  * If the substitution character array is too small, an
    602  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.
    603  * @see ucnv_setSubstString
    604  * @see ucnv_setSubstChars
    605  * @stable ICU 2.0
    606  */
    607 U_STABLE void U_EXPORT2
    608 ucnv_getSubstChars(const UConverter *converter,
    609                    char *subChars,
    610                    int8_t *len,
    611                    UErrorCode *err);
    612 
    613 /**
    614  * Sets the substitution chars when converting from unicode to a codepage. The
    615  * substitution is specified as a string of 1-4 bytes, and may contain
    616  * <TT>NULL</TT> bytes.
    617  * The subChars must represent a single character. The caller needs to know the
    618  * byte sequence of a valid character in the converter's charset.
    619  * For some converters, for example some ISO 2022 variants, only single-byte
    620  * substitution characters may be supported.
    621  * The newer ucnv_setSubstString() function relaxes these limitations.
    622  *
    623  * @param converter the Unicode converter
    624  * @param subChars the substitution character byte sequence we want set
    625  * @param len the number of bytes in subChars
    626  * @param err the error status code.  <TT>U_INDEX_OUTOFBOUNDS_ERROR </TT> if
    627  * len is bigger than the maximum number of bytes allowed in subchars
    628  * @see ucnv_setSubstString
    629  * @see ucnv_getSubstChars
    630  * @stable ICU 2.0
    631  */
    632 U_STABLE void U_EXPORT2
    633 ucnv_setSubstChars(UConverter *converter,
    634                    const char *subChars,
    635                    int8_t len,
    636                    UErrorCode *err);
    637 
    638 /**
    639  * Set a substitution string for converting from Unicode to a charset.
    640  * The caller need not know the charset byte sequence for each charset.
    641  *
    642  * Unlike ucnv_setSubstChars() which is designed to set a charset byte sequence
    643  * for a single character, this function takes a Unicode string with
    644  * zero, one or more characters, and immediately verifies that the string can be
    645  * converted to the charset.
    646  * If not, or if the result is too long (more than 32 bytes as of ICU 3.6),
    647  * then the function returns with an error accordingly.
    648  *
    649  * Also unlike ucnv_setSubstChars(), this function works for stateful charsets
    650  * by converting on the fly at the point of substitution rather than setting
    651  * a fixed byte sequence.
    652  *
    653  * @param cnv The UConverter object.
    654  * @param s The Unicode string.
    655  * @param length The number of UChars in s, or -1 for a NUL-terminated string.
    656  * @param err Pointer to a standard ICU error code. Its input value must
    657  *            pass the U_SUCCESS() test, or else the function returns
    658  *            immediately. Check for U_FAILURE() on output or use with
    659  *            function chaining. (See User Guide for details.)
    660  *
    661  * @see ucnv_setSubstChars
    662  * @see ucnv_getSubstChars
    663  * @stable ICU 3.6
    664  */
    665 U_STABLE void U_EXPORT2
    666 ucnv_setSubstString(UConverter *cnv,
    667                     const UChar *s,
    668                     int32_t length,
    669                     UErrorCode *err);
    670 
    671 /**
    672  * Fills in the output parameter, errBytes, with the error characters from the
    673  * last failing conversion.
    674  *
    675  * @param converter the Unicode converter
    676  * @param errBytes the codepage bytes which were in error
    677  * @param len on input the capacity of errBytes, on output the number of
    678  *  bytes which were copied to it
    679  * @param err the error status code.
    680  * If the substitution character array is too small, an
    681  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.
    682  * @stable ICU 2.0
    683  */
    684 U_STABLE void U_EXPORT2
    685 ucnv_getInvalidChars(const UConverter *converter,
    686                      char *errBytes,
    687                      int8_t *len,
    688                      UErrorCode *err);
    689 
    690 /**
    691  * Fills in the output parameter, errChars, with the error characters from the
    692  * last failing conversion.
    693  *
    694  * @param converter the Unicode converter
    695  * @param errUChars the UChars which were in error
    696  * @param len on input the capacity of errUChars, on output the number of
    697  *  UChars which were copied to it
    698  * @param err the error status code.
    699  * If the substitution character array is too small, an
    700  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.
    701  * @stable ICU 2.0
    702  */
    703 U_STABLE void U_EXPORT2
    704 ucnv_getInvalidUChars(const UConverter *converter,
    705                       UChar *errUChars,
    706                       int8_t *len,
    707                       UErrorCode *err);
    708 
    709 /**
    710  * Resets the state of a converter to the default state. This is used
    711  * in the case of an error, to restart a conversion from a known default state.
    712  * It will also empty the internal output buffers.
    713  * @param converter the Unicode converter
    714  * @stable ICU 2.0
    715  */
    716 U_STABLE void U_EXPORT2
    717 ucnv_reset(UConverter *converter);
    718 
    719 /**
    720  * Resets the to-Unicode part of a converter state to the default state.
    721  * This is used in the case of an error to restart a conversion to
    722  * Unicode to a known default state. It will also empty the internal
    723  * output buffers used for the conversion to Unicode codepoints.
    724  * @param converter the Unicode converter
    725  * @stable ICU 2.0
    726  */
    727 U_STABLE void U_EXPORT2
    728 ucnv_resetToUnicode(UConverter *converter);
    729 
    730 /**
    731  * Resets the from-Unicode part of a converter state to the default state.
    732  * This is used in the case of an error to restart a conversion from
    733  * Unicode to a known default state. It will also empty the internal output
    734  * buffers used for the conversion from Unicode codepoints.
    735  * @param converter the Unicode converter
    736  * @stable ICU 2.0
    737  */
    738 U_STABLE void U_EXPORT2
    739 ucnv_resetFromUnicode(UConverter *converter);
    740 
    741 /**
    742  * Returns the maximum number of bytes that are output per UChar in conversion
    743  * from Unicode using this converter.
    744  * The returned number can be used with UCNV_GET_MAX_BYTES_FOR_STRING
    745  * to calculate the size of a target buffer for conversion from Unicode.
    746  *
    747  * Note: Before ICU 2.8, this function did not return reliable numbers for
    748  * some stateful converters (EBCDIC_STATEFUL, ISO-2022) and LMBCS.
    749  *
    750  * This number may not be the same as the maximum number of bytes per
    751  * "conversion unit". In other words, it may not be the intuitively expected
    752  * number of bytes per character that would be published for a charset,
    753  * and may not fulfill any other purpose than the allocation of an output
    754  * buffer of guaranteed sufficient size for a given input length and converter.
    755  *
    756  * Examples for special cases that are taken into account:
    757  * - Supplementary code points may convert to more bytes than BMP code points.
    758  *   This function returns bytes per UChar (UTF-16 code unit), not per
    759  *   Unicode code point, for efficient buffer allocation.
    760  * - State-shifting output (SI/SO, escapes, etc.) from stateful converters.
    761  * - When m input UChars are converted to n output bytes, then the maximum m/n
    762  *   is taken into account.
    763  *
    764  * The number returned here does not take into account
    765  * (see UCNV_GET_MAX_BYTES_FOR_STRING):
    766  * - callbacks which output more than one charset character sequence per call,
    767  *   like escape callbacks
    768  * - initial and final non-character bytes that are output by some converters
    769  *   (automatic BOMs, initial escape sequence, final SI, etc.)
    770  *
    771  * Examples for returned values:
    772  * - SBCS charsets: 1
    773  * - Shift-JIS: 2
    774  * - UTF-16: 2 (2 per BMP, 4 per surrogate _pair_, BOM not counted)
    775  * - UTF-8: 3 (3 per BMP, 4 per surrogate _pair_)
    776  * - EBCDIC_STATEFUL (EBCDIC mixed SBCS/DBCS): 3 (SO + DBCS)
    777  * - ISO-2022: 3 (always outputs UTF-8)
    778  * - ISO-2022-JP: 6 (4-byte escape sequences + DBCS)
    779  * - ISO-2022-CN: 8 (4-byte designator sequences + 2-byte SS2/SS3 + DBCS)
    780  *
    781  * @param converter The Unicode converter.
    782  * @return The maximum number of bytes per UChar (16 bit code unit)
    783  *    that are output by ucnv_fromUnicode(),
    784  *    to be used together with UCNV_GET_MAX_BYTES_FOR_STRING
    785  *    for buffer allocation.
    786  *
    787  * @see UCNV_GET_MAX_BYTES_FOR_STRING
    788  * @see ucnv_getMinCharSize
    789  * @stable ICU 2.0
    790  */
    791 U_STABLE int8_t U_EXPORT2
    792 ucnv_getMaxCharSize(const UConverter *converter);
    793 
    794 /**
    795  * Calculates the size of a buffer for conversion from Unicode to a charset.
    796  * The calculated size is guaranteed to be sufficient for this conversion.
    797  *
    798  * It takes into account initial and final non-character bytes that are output
    799  * by some converters.
    800  * It does not take into account callbacks which output more than one charset
    801  * character sequence per call, like escape callbacks.
    802  * The default (substitution) callback only outputs one charset character sequence.
    803  *
    804  * @param length Number of UChars to be converted.
    805  * @param maxCharSize Return value from ucnv_getMaxCharSize() for the converter
    806  *                    that will be used.
    807  * @return Size of a buffer that will be large enough to hold the output bytes of
    808  *         converting length UChars with the converter that returned the maxCharSize.
    809  *
    810  * @see ucnv_getMaxCharSize
    811  * @stable ICU 2.8
    812  */
    813 #define UCNV_GET_MAX_BYTES_FOR_STRING(length, maxCharSize) \
    814      (((int32_t)(length)+10)*(int32_t)(maxCharSize))
    815 
    816 /**
    817  * Returns the minimum byte length (per codepoint) for characters in this codepage.
    818  * This is usually either 1 or 2.
    819  * @param converter the Unicode converter
    820  * @return the minimum number of bytes per codepoint allowed by this particular converter
    821  * @see ucnv_getMaxCharSize
    822  * @stable ICU 2.0
    823  */
    824 U_STABLE int8_t U_EXPORT2
    825 ucnv_getMinCharSize(const UConverter *converter);
    826 
    827 /**
    828  * Returns the display name of the converter passed in based on the Locale
    829  * passed in. If the locale contains no display name, the internal ASCII
    830  * name will be filled in.
    831  *
    832  * @param converter the Unicode converter.
    833  * @param displayLocale is the specific Locale we want to localised for
    834  * @param displayName user provided buffer to be filled in
    835  * @param displayNameCapacity size of displayName Buffer
    836  * @param err error status code
    837  * @return displayNameLength number of UChar needed in displayName
    838  * @see ucnv_getName
    839  * @stable ICU 2.0
    840  */
    841 U_STABLE int32_t U_EXPORT2
    842 ucnv_getDisplayName(const UConverter *converter,
    843                     const char *displayLocale,
    844                     UChar *displayName,
    845                     int32_t displayNameCapacity,
    846                     UErrorCode *err);
    847 
    848 /**
    849  * Gets the internal, canonical name of the converter (zero-terminated).
    850  * The lifetime of the returned string will be that of the converter
    851  * passed to this function.
    852  * @param converter the Unicode converter
    853  * @param err UErrorCode status
    854  * @return the internal name of the converter
    855  * @see ucnv_getDisplayName
    856  * @stable ICU 2.0
    857  */
    858 U_STABLE const char * U_EXPORT2
    859 ucnv_getName(const UConverter *converter, UErrorCode *err);
    860 
    861 /**
    862  * Gets a codepage number associated with the converter. This is not guaranteed
    863  * to be the one used to create the converter. Some converters do not represent
    864  * platform registered codepages and return zero for the codepage number.
    865  * The error code fill-in parameter indicates if the codepage number
    866  * is available.
    867  * Does not check if the converter is <TT>NULL</TT> or if converter's data
    868  * table is <TT>NULL</TT>.
    869  *
    870  * Important: The use of CCSIDs is not recommended because it is limited
    871  * to only two platforms in principle and only one (UCNV_IBM) in the current
    872  * ICU converter API.
    873  * Also, CCSIDs are insufficient to identify IBM Unicode conversion tables precisely.
    874  * For more details see ucnv_openCCSID().
    875  *
    876  * @param converter the Unicode converter
    877  * @param err the error status code.
    878  * @return If any error occurrs, -1 will be returned otherwise, the codepage number
    879  * will be returned
    880  * @see ucnv_openCCSID
    881  * @see ucnv_getPlatform
    882  * @stable ICU 2.0
    883  */
    884 U_STABLE int32_t U_EXPORT2
    885 ucnv_getCCSID(const UConverter *converter,
    886               UErrorCode *err);
    887 
    888 /**
    889  * Gets a codepage platform associated with the converter. Currently,
    890  * only <TT>UCNV_IBM</TT> will be returned.
    891  * Does not test if the converter is <TT>NULL</TT> or if converter's data
    892  * table is <TT>NULL</TT>.
    893  * @param converter the Unicode converter
    894  * @param err the error status code.
    895  * @return The codepage platform
    896  * @stable ICU 2.0
    897  */
    898 U_STABLE UConverterPlatform U_EXPORT2
    899 ucnv_getPlatform(const UConverter *converter,
    900                  UErrorCode *err);
    901 
    902 /**
    903  * Gets the type of the converter
    904  * e.g. SBCS, MBCS, DBCS, UTF8, UTF16_BE, UTF16_LE, ISO_2022,
    905  * EBCDIC_STATEFUL, LATIN_1
    906  * @param converter a valid, opened converter
    907  * @return the type of the converter
    908  * @stable ICU 2.0
    909  */
    910 U_STABLE UConverterType U_EXPORT2
    911 ucnv_getType(const UConverter * converter);
    912 
    913 /**
    914  * Gets the "starter" (lead) bytes for converters of type MBCS.
    915  * Will fill in an <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> if converter passed in
    916  * is not MBCS. Fills in an array of type UBool, with the value of the byte
    917  * as offset to the array. For example, if (starters[0x20] == TRUE) at return,
    918  * it means that the byte 0x20 is a starter byte in this converter.
    919  * Context pointers are always owned by the caller.
    920  *
    921  * @param converter a valid, opened converter of type MBCS
    922  * @param starters an array of size 256 to be filled in
    923  * @param err error status, <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> if the
    924  * converter is not a type which can return starters.
    925  * @see ucnv_getType
    926  * @stable ICU 2.0
    927  */
    928 U_STABLE void U_EXPORT2
    929 ucnv_getStarters(const UConverter* converter,
    930                  UBool starters[256],
    931                  UErrorCode* err);
    932 
    933 
    934 /**
    935  * Selectors for Unicode sets that can be returned by ucnv_getUnicodeSet().
    936  * @see ucnv_getUnicodeSet
    937  * @stable ICU 2.6
    938  */
    939 typedef enum UConverterUnicodeSet {
    940     /** Select the set of roundtrippable Unicode code points. @stable ICU 2.6 */
    941     UCNV_ROUNDTRIP_SET,
    942     /** Select the set of Unicode code points with roundtrip or fallback mappings. @stable ICU 4.0 */
    943     UCNV_ROUNDTRIP_AND_FALLBACK_SET,
    944     /** Number of UConverterUnicodeSet selectors. @stable ICU 2.6 */
    945     UCNV_SET_COUNT
    946 } UConverterUnicodeSet;
    947 
    948 
    949 /**
    950  * Returns the set of Unicode code points that can be converted by an ICU converter.
    951  *
    952  * Returns one of several kinds of set:
    953  *
    954  * 1. UCNV_ROUNDTRIP_SET
    955  *
    956  * The set of all Unicode code points that can be roundtrip-converted
    957  * (converted without any data loss) with the converter (ucnv_fromUnicode()).
    958  * This set will not include code points that have fallback mappings
    959  * or are only the result of reverse fallback mappings.
    960  * This set will also not include PUA code points with fallbacks, although
    961  * ucnv_fromUnicode() will always uses those mappings despite ucnv_setFallback().
    962  * See UTR #22 "Character Mapping Markup Language"
    963  * at http://www.unicode.org/reports/tr22/
    964  *
    965  * This is useful for example for
    966  * - checking that a string or document can be roundtrip-converted with a converter,
    967  *   without/before actually performing the conversion
    968  * - testing if a converter can be used for text for typical text for a certain locale,
    969  *   by comparing its roundtrip set with the set of ExemplarCharacters from
    970  *   ICU's locale data or other sources
    971  *
    972  * 2. UCNV_ROUNDTRIP_AND_FALLBACK_SET
    973  *
    974  * The set of all Unicode code points that can be converted with the converter (ucnv_fromUnicode())
    975  * when fallbacks are turned on (see ucnv_setFallback()).
    976  * This set includes all code points with roundtrips and fallbacks (but not reverse fallbacks).
    977  *
    978  * In the future, there may be more UConverterUnicodeSet choices to select
    979  * sets with different properties.
    980  *
    981  * @param cnv The converter for which a set is requested.
    982  * @param setFillIn A valid USet *. It will be cleared by this function before
    983  *            the converter's specific set is filled into the USet.
    984  * @param whichSet A UConverterUnicodeSet selector;
    985  *              currently UCNV_ROUNDTRIP_SET is the only supported value.
    986  * @param pErrorCode ICU error code in/out parameter.
    987  *                   Must fulfill U_SUCCESS before the function call.
    988  *
    989  * @see UConverterUnicodeSet
    990  * @see uset_open
    991  * @see uset_close
    992  * @stable ICU 2.6
    993  */
    994 U_STABLE void U_EXPORT2
    995 ucnv_getUnicodeSet(const UConverter *cnv,
    996                    USet *setFillIn,
    997                    UConverterUnicodeSet whichSet,
    998                    UErrorCode *pErrorCode);
    999 
   1000 /**
   1001  * Gets the current calback function used by the converter when an illegal
   1002  *  or invalid codepage sequence is found.
   1003  * Context pointers are always owned by the caller.
   1004  *
   1005  * @param converter the unicode converter
   1006  * @param action fillin: returns the callback function pointer
   1007  * @param context fillin: returns the callback's private void* context
   1008  * @see ucnv_setToUCallBack
   1009  * @stable ICU 2.0
   1010  */
   1011 U_STABLE void U_EXPORT2
   1012 ucnv_getToUCallBack (const UConverter * converter,
   1013                      UConverterToUCallback *action,
   1014                      const void **context);
   1015 
   1016 /**
   1017  * Gets the current callback function used by the converter when illegal
   1018  * or invalid Unicode sequence is found.
   1019  * Context pointers are always owned by the caller.
   1020  *
   1021  * @param converter the unicode converter
   1022  * @param action fillin: returns the callback function pointer
   1023  * @param context fillin: returns the callback's private void* context
   1024  * @see ucnv_setFromUCallBack
   1025  * @stable ICU 2.0
   1026  */
   1027 U_STABLE void U_EXPORT2
   1028 ucnv_getFromUCallBack (const UConverter * converter,
   1029                        UConverterFromUCallback *action,
   1030                        const void **context);
   1031 
   1032 /**
   1033  * Changes the callback function used by the converter when
   1034  * an illegal or invalid sequence is found.
   1035  * Context pointers are always owned by the caller.
   1036  * Predefined actions and contexts can be found in the ucnv_err.h header.
   1037  *
   1038  * @param converter the unicode converter
   1039  * @param newAction the new callback function
   1040  * @param newContext the new toUnicode callback context pointer. This can be NULL.
   1041  * @param oldAction fillin: returns the old callback function pointer. This can be NULL.
   1042  * @param oldContext fillin: returns the old callback's private void* context. This can be NULL.
   1043  * @param err The error code status
   1044  * @see ucnv_getToUCallBack
   1045  * @stable ICU 2.0
   1046  */
   1047 U_STABLE void U_EXPORT2
   1048 ucnv_setToUCallBack (UConverter * converter,
   1049                      UConverterToUCallback newAction,
   1050                      const void* newContext,
   1051                      UConverterToUCallback *oldAction,
   1052                      const void** oldContext,
   1053                      UErrorCode * err);
   1054 
   1055 /**
   1056  * Changes the current callback function used by the converter when
   1057  * an illegal or invalid sequence is found.
   1058  * Context pointers are always owned by the caller.
   1059  * Predefined actions and contexts can be found in the ucnv_err.h header.
   1060  *
   1061  * @param converter the unicode converter
   1062  * @param newAction the new callback function
   1063  * @param newContext the new fromUnicode callback context pointer. This can be NULL.
   1064  * @param oldAction fillin: returns the old callback function pointer. This can be NULL.
   1065  * @param oldContext fillin: returns the old callback's private void* context. This can be NULL.
   1066  * @param err The error code status
   1067  * @see ucnv_getFromUCallBack
   1068  * @stable ICU 2.0
   1069  */
   1070 U_STABLE void U_EXPORT2
   1071 ucnv_setFromUCallBack (UConverter * converter,
   1072                        UConverterFromUCallback newAction,
   1073                        const void *newContext,
   1074                        UConverterFromUCallback *oldAction,
   1075                        const void **oldContext,
   1076                        UErrorCode * err);
   1077 
   1078 /**
   1079  * Converts an array of unicode characters to an array of codepage
   1080  * characters. This function is optimized for converting a continuous
   1081  * stream of data in buffer-sized chunks, where the entire source and
   1082  * target does not fit in available buffers.
   1083  *
   1084  * The source pointer is an in/out parameter. It starts out pointing where the
   1085  * conversion is to begin, and ends up pointing after the last UChar consumed.
   1086  *
   1087  * Target similarly starts out pointer at the first available byte in the output
   1088  * buffer, and ends up pointing after the last byte written to the output.
   1089  *
   1090  * The converter always attempts to consume the entire source buffer, unless
   1091  * (1.) the target buffer is full, or (2.) a failing error is returned from the
   1092  * current callback function.  When a successful error status has been
   1093  * returned, it means that all of the source buffer has been
   1094  *  consumed. At that point, the caller should reset the source and
   1095  *  sourceLimit pointers to point to the next chunk.
   1096  *
   1097  * At the end of the stream (flush==TRUE), the input is completely consumed
   1098  * when *source==sourceLimit and no error code is set.
   1099  * The converter object is then automatically reset by this function.
   1100  * (This means that a converter need not be reset explicitly between data
   1101  * streams if it finishes the previous stream without errors.)
   1102  *
   1103  * This is a <I>stateful</I> conversion. Additionally, even when all source data has
   1104  * been consumed, some data may be in the converters' internal state.
   1105  * Call this function repeatedly, updating the target pointers with
   1106  * the next empty chunk of target in case of a
   1107  * <TT>U_BUFFER_OVERFLOW_ERROR</TT>, and updating the source  pointers
   1108  *  with the next chunk of source when a successful error status is
   1109  * returned, until there are no more chunks of source data.
   1110  * @param converter the Unicode converter
   1111  * @param target I/O parameter. Input : Points to the beginning of the buffer to copy
   1112  *  codepage characters to. Output : points to after the last codepage character copied
   1113  *  to <TT>target</TT>.
   1114  * @param targetLimit the pointer just after last of the <TT>target</TT> buffer
   1115  * @param source I/O parameter, pointer to pointer to the source Unicode character buffer.
   1116  * @param sourceLimit the pointer just after the last of the source buffer
   1117  * @param offsets if NULL is passed, nothing will happen to it, otherwise it needs to have the same number
   1118  * of allocated cells as <TT>target</TT>. Will fill in offsets from target to source pointer
   1119  * e.g: <TT>offsets[3]</TT> is equal to 6, it means that the <TT>target[3]</TT> was a result of transcoding <TT>source[6]</TT>
   1120  * For output data carried across calls, and other data without a specific source character
   1121  * (such as from escape sequences or callbacks)  -1 will be placed for offsets.
   1122  * @param flush set to <TT>TRUE</TT> if the current source buffer is the last available
   1123  * chunk of the source, <TT>FALSE</TT> otherwise. Note that if a failing status is returned,
   1124  * this function may have to be called multiple times with flush set to <TT>TRUE</TT> until
   1125  * the source buffer is consumed.
   1126  * @param err the error status.  <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> will be set if the
   1127  * converter is <TT>NULL</TT>.
   1128  * <code>U_BUFFER_OVERFLOW_ERROR</code> will be set if the target is full and there is
   1129  * still data to be written to the target.
   1130  * @see ucnv_fromUChars
   1131  * @see ucnv_convert
   1132  * @see ucnv_getMinCharSize
   1133  * @see ucnv_setToUCallBack
   1134  * @stable ICU 2.0
   1135  */
   1136 U_STABLE void U_EXPORT2
   1137 ucnv_fromUnicode (UConverter * converter,
   1138                   char **target,
   1139                   const char *targetLimit,
   1140                   const UChar ** source,
   1141                   const UChar * sourceLimit,
   1142                   int32_t* offsets,
   1143                   UBool flush,
   1144                   UErrorCode * err);
   1145 
   1146 /**
   1147  * Converts a buffer of codepage bytes into an array of unicode UChars
   1148  * characters. This function is optimized for converting a continuous
   1149  * stream of data in buffer-sized chunks, where the entire source and
   1150  * target does not fit in available buffers.
   1151  *
   1152  * The source pointer is an in/out parameter. It starts out pointing where the
   1153  * conversion is to begin, and ends up pointing after the last byte of source consumed.
   1154  *
   1155  * Target similarly starts out pointer at the first available UChar in the output
   1156  * buffer, and ends up pointing after the last UChar written to the output.
   1157  * It does NOT necessarily keep UChar sequences together.
   1158  *
   1159  * The converter always attempts to consume the entire source buffer, unless
   1160  * (1.) the target buffer is full, or (2.) a failing error is returned from the
   1161  * current callback function.  When a successful error status has been
   1162  * returned, it means that all of the source buffer has been
   1163  *  consumed. At that point, the caller should reset the source and
   1164  *  sourceLimit pointers to point to the next chunk.
   1165  *
   1166  * At the end of the stream (flush==TRUE), the input is completely consumed
   1167  * when *source==sourceLimit and no error code is set
   1168  * The converter object is then automatically reset by this function.
   1169  * (This means that a converter need not be reset explicitly between data
   1170  * streams if it finishes the previous stream without errors.)
   1171  *
   1172  * This is a <I>stateful</I> conversion. Additionally, even when all source data has
   1173  * been consumed, some data may be in the converters' internal state.
   1174  * Call this function repeatedly, updating the target pointers with
   1175  * the next empty chunk of target in case of a
   1176  * <TT>U_BUFFER_OVERFLOW_ERROR</TT>, and updating the source  pointers
   1177  *  with the next chunk of source when a successful error status is
   1178  * returned, until there are no more chunks of source data.
   1179  * @param converter the Unicode converter
   1180  * @param target I/O parameter. Input : Points to the beginning of the buffer to copy
   1181  *  UChars into. Output : points to after the last UChar copied.
   1182  * @param targetLimit the pointer just after the end of the <TT>target</TT> buffer
   1183  * @param source I/O parameter, pointer to pointer to the source codepage buffer.
   1184  * @param sourceLimit the pointer to the byte after the end of the source buffer
   1185  * @param offsets if NULL is passed, nothing will happen to it, otherwise it needs to have the same number
   1186  * of allocated cells as <TT>target</TT>. Will fill in offsets from target to source pointer
   1187  * e.g: <TT>offsets[3]</TT> is equal to 6, it means that the <TT>target[3]</TT> was a result of transcoding <TT>source[6]</TT>
   1188  * For output data carried across calls, and other data without a specific source character
   1189  * (such as from escape sequences or callbacks)  -1 will be placed for offsets.
   1190  * @param flush set to <TT>TRUE</TT> if the current source buffer is the last available
   1191  * chunk of the source, <TT>FALSE</TT> otherwise. Note that if a failing status is returned,
   1192  * this function may have to be called multiple times with flush set to <TT>TRUE</TT> until
   1193  * the source buffer is consumed.
   1194  * @param err the error status.  <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> will be set if the
   1195  * converter is <TT>NULL</TT>.
   1196  * <code>U_BUFFER_OVERFLOW_ERROR</code> will be set if the target is full and there is
   1197  * still data to be written to the target.
   1198  * @see ucnv_fromUChars
   1199  * @see ucnv_convert
   1200  * @see ucnv_getMinCharSize
   1201  * @see ucnv_setFromUCallBack
   1202  * @see ucnv_getNextUChar
   1203  * @stable ICU 2.0
   1204  */
   1205 U_STABLE void U_EXPORT2
   1206 ucnv_toUnicode(UConverter *converter,
   1207                UChar **target,
   1208                const UChar *targetLimit,
   1209                const char **source,
   1210                const char *sourceLimit,
   1211                int32_t *offsets,
   1212                UBool flush,
   1213                UErrorCode *err);
   1214 
   1215 /**
   1216  * Convert the Unicode string into a codepage string using an existing UConverter.
   1217  * The output string is NUL-terminated if possible.
   1218  *
   1219  * This function is a more convenient but less powerful version of ucnv_fromUnicode().
   1220  * It is only useful for whole strings, not for streaming conversion.
   1221  *
   1222  * The maximum output buffer capacity required (barring output from callbacks) will be
   1223  * UCNV_GET_MAX_BYTES_FOR_STRING(srcLength, ucnv_getMaxCharSize(cnv)).
   1224  *
   1225  * @param cnv the converter object to be used (ucnv_resetFromUnicode() will be called)
   1226  * @param src the input Unicode string
   1227  * @param srcLength the input string length, or -1 if NUL-terminated
   1228  * @param dest destination string buffer, can be NULL if destCapacity==0
   1229  * @param destCapacity the number of chars available at dest
   1230  * @param pErrorCode normal ICU error code;
   1231  *                  common error codes that may be set by this function include
   1232  *                  U_BUFFER_OVERFLOW_ERROR, U_STRING_NOT_TERMINATED_WARNING,
   1233  *                  U_ILLEGAL_ARGUMENT_ERROR, and conversion errors
   1234  * @return the length of the output string, not counting the terminating NUL;
   1235  *         if the length is greater than destCapacity, then the string will not fit
   1236  *         and a buffer of the indicated length would need to be passed in
   1237  * @see ucnv_fromUnicode
   1238  * @see ucnv_convert
   1239  * @see UCNV_GET_MAX_BYTES_FOR_STRING
   1240  * @stable ICU 2.0
   1241  */
   1242 U_STABLE int32_t U_EXPORT2
   1243 ucnv_fromUChars(UConverter *cnv,
   1244                 char *dest, int32_t destCapacity,
   1245                 const UChar *src, int32_t srcLength,
   1246                 UErrorCode *pErrorCode);
   1247 
   1248 /**
   1249  * Convert the codepage string into a Unicode string using an existing UConverter.
   1250  * The output string is NUL-terminated if possible.
   1251  *
   1252  * This function is a more convenient but less powerful version of ucnv_toUnicode().
   1253  * It is only useful for whole strings, not for streaming conversion.
   1254  *
   1255  * The maximum output buffer capacity required (barring output from callbacks) will be
   1256  * 2*srcLength (each char may be converted into a surrogate pair).
   1257  *
   1258  * @param cnv the converter object to be used (ucnv_resetToUnicode() will be called)
   1259  * @param src the input codepage string
   1260  * @param srcLength the input string length, or -1 if NUL-terminated
   1261  * @param dest destination string buffer, can be NULL if destCapacity==0
   1262  * @param destCapacity the number of UChars available at dest
   1263  * @param pErrorCode normal ICU error code;
   1264  *                  common error codes that may be set by this function include
   1265  *                  U_BUFFER_OVERFLOW_ERROR, U_STRING_NOT_TERMINATED_WARNING,
   1266  *                  U_ILLEGAL_ARGUMENT_ERROR, and conversion errors
   1267  * @return the length of the output string, not counting the terminating NUL;
   1268  *         if the length is greater than destCapacity, then the string will not fit
   1269  *         and a buffer of the indicated length would need to be passed in
   1270  * @see ucnv_toUnicode
   1271  * @see ucnv_convert
   1272  * @stable ICU 2.0
   1273  */
   1274 U_STABLE int32_t U_EXPORT2
   1275 ucnv_toUChars(UConverter *cnv,
   1276               UChar *dest, int32_t destCapacity,
   1277               const char *src, int32_t srcLength,
   1278               UErrorCode *pErrorCode);
   1279 
   1280 /**
   1281  * Convert a codepage buffer into Unicode one character at a time.
   1282  * The input is completely consumed when the U_INDEX_OUTOFBOUNDS_ERROR is set.
   1283  *
   1284  * Advantage compared to ucnv_toUnicode() or ucnv_toUChars():
   1285  * - Faster for small amounts of data, for most converters, e.g.,
   1286  *   US-ASCII, ISO-8859-1, UTF-8/16/32, and most "normal" charsets.
   1287  *   (For complex converters, e.g., SCSU, UTF-7 and ISO 2022 variants,
   1288  *    it uses ucnv_toUnicode() internally.)
   1289  * - Convenient.
   1290  *
   1291  * Limitations compared to ucnv_toUnicode():
   1292  * - Always assumes flush=TRUE.
   1293  *   This makes ucnv_getNextUChar() unsuitable for "streaming" conversion,
   1294  *   that is, for where the input is supplied in multiple buffers,
   1295  *   because ucnv_getNextUChar() will assume the end of the input at the end
   1296  *   of the first buffer.
   1297  * - Does not provide offset output.
   1298  *
   1299  * It is possible to "mix" ucnv_getNextUChar() and ucnv_toUnicode() because
   1300  * ucnv_getNextUChar() uses the current state of the converter
   1301  * (unlike ucnv_toUChars() which always resets first).
   1302  * However, if ucnv_getNextUChar() is called after ucnv_toUnicode()
   1303  * stopped in the middle of a character sequence (with flush=FALSE),
   1304  * then ucnv_getNextUChar() will always use the slower ucnv_toUnicode()
   1305  * internally until the next character boundary.
   1306  * (This is new in ICU 2.6. In earlier releases, ucnv_getNextUChar() had to
   1307  * start at a character boundary.)
   1308  *
   1309  * Instead of using ucnv_getNextUChar(), it is recommended
   1310  * to convert using ucnv_toUnicode() or ucnv_toUChars()
   1311  * and then iterate over the text using U16_NEXT() or a UCharIterator (uiter.h)
   1312  * or a C++ CharacterIterator or similar.
   1313  * This allows streaming conversion and offset output, for example.
   1314  *
   1315  * <p>Handling of surrogate pairs and supplementary-plane code points:<br>
   1316  * There are two different kinds of codepages that provide mappings for surrogate characters:
   1317  * <ul>
   1318  *   <li>Codepages like UTF-8, UTF-32, and GB 18030 provide direct representations for Unicode
   1319  *       code points U+10000-U+10ffff as well as for single surrogates U+d800-U+dfff.
   1320  *       Each valid sequence will result in exactly one returned code point.
   1321  *       If a sequence results in a single surrogate, then that will be returned
   1322  *       by itself, even if a neighboring sequence encodes the matching surrogate.</li>
   1323  *   <li>Codepages like SCSU and LMBCS (and UTF-16) provide direct representations only for BMP code points
   1324  *       including surrogates. Code points in supplementary planes are represented with
   1325  *       two sequences, each encoding a surrogate.
   1326  *       For these codepages, matching pairs of surrogates will be combined into single
   1327  *       code points for returning from this function.
   1328  *       (Note that SCSU is actually a mix of these codepage types.)</li>
   1329  * </ul></p>
   1330  *
   1331  * @param converter an open UConverter
   1332  * @param source the address of a pointer to the codepage buffer, will be
   1333  *  updated to point after the bytes consumed in the conversion call.
   1334  * @param sourceLimit points to the end of the input buffer
   1335  * @param err fills in error status (see ucnv_toUnicode)
   1336  * <code>U_INDEX_OUTOFBOUNDS_ERROR</code> will be set if the input
   1337  * is empty or does not convert to any output (e.g.: pure state-change
   1338  * codes SI/SO, escape sequences for ISO 2022,
   1339  * or if the callback did not output anything, ...).
   1340  * This function will not set a <code>U_BUFFER_OVERFLOW_ERROR</code> because
   1341  *  the "buffer" is the return code. However, there might be subsequent output
   1342  *  stored in the converter object
   1343  * that will be returned in following calls to this function.
   1344  * @return a UChar32 resulting from the partial conversion of source
   1345  * @see ucnv_toUnicode
   1346  * @see ucnv_toUChars
   1347  * @see ucnv_convert
   1348  * @stable ICU 2.0
   1349  */
   1350 U_STABLE UChar32 U_EXPORT2
   1351 ucnv_getNextUChar(UConverter * converter,
   1352                   const char **source,
   1353                   const char * sourceLimit,
   1354                   UErrorCode * err);
   1355 
   1356 /**
   1357  * Convert from one external charset to another using two existing UConverters.
   1358  * Internally, two conversions - ucnv_toUnicode() and ucnv_fromUnicode() -
   1359  * are used, "pivoting" through 16-bit Unicode.
   1360  *
   1361  * Important: For streaming conversion (multiple function calls for successive
   1362  * parts of a text stream), the caller must provide a pivot buffer explicitly,
   1363  * and must preserve the pivot buffer and associated pointers from one
   1364  * call to another. (The buffer may be moved if its contents and the relative
   1365  * pointer positions are preserved.)
   1366  *
   1367  * There is a similar function, ucnv_convert(),
   1368  * which has the following limitations:
   1369  * - it takes charset names, not converter objects, so that
   1370  *   - two converters are opened for each call
   1371  *   - only single-string conversion is possible, not streaming operation
   1372  * - it does not provide enough information to find out,
   1373  *   in case of failure, whether the toUnicode or
   1374  *   the fromUnicode conversion failed
   1375  *
   1376  * By contrast, ucnv_convertEx()
   1377  * - takes UConverter parameters instead of charset names
   1378  * - fully exposes the pivot buffer for streaming conversion and complete error handling
   1379  *
   1380  * ucnv_convertEx() also provides further convenience:
   1381  * - an option to reset the converters at the beginning
   1382  *   (if reset==TRUE, see parameters;
   1383  *    also sets *pivotTarget=*pivotSource=pivotStart)
   1384  * - allow NUL-terminated input
   1385  *   (only a single NUL byte, will not work for charsets with multi-byte NULs)
   1386  *   (if sourceLimit==NULL, see parameters)
   1387  * - terminate with a NUL on output
   1388  *   (only a single NUL byte, not useful for charsets with multi-byte NULs),
   1389  *   or set U_STRING_NOT_TERMINATED_WARNING if the output exactly fills
   1390  *   the target buffer
   1391  * - the pivot buffer can be provided internally;
   1392  *   possible only for whole-string conversion, not streaming conversion;
   1393  *   in this case, the caller will not be able to get details about where an
   1394  *   error occurred
   1395  *   (if pivotStart==NULL, see below)
   1396  *
   1397  * The function returns when one of the following is true:
   1398  * - the entire source text has been converted successfully to the target buffer
   1399  * - a target buffer overflow occurred (U_BUFFER_OVERFLOW_ERROR)
   1400  * - a conversion error occurred
   1401  *   (other U_FAILURE(), see description of pErrorCode)
   1402  *
   1403  * Limitation compared to the direct use of
   1404  * ucnv_fromUnicode() and ucnv_toUnicode():
   1405  * ucnv_convertEx() does not provide offset information.
   1406  *
   1407  * Limitation compared to ucnv_fromUChars() and ucnv_toUChars():
   1408  * ucnv_convertEx() does not support preflighting directly.
   1409  *
   1410  * Sample code for converting a single string from
   1411  * one external charset to UTF-8, ignoring the location of errors:
   1412  *
   1413  * \code
   1414  * int32_t
   1415  * myToUTF8(UConverter *cnv,
   1416  *          const char *s, int32_t length,
   1417  *          char *u8, int32_t capacity,
   1418  *          UErrorCode *pErrorCode) {
   1419  *     UConverter *utf8Cnv;
   1420  *     char *target;
   1421  *
   1422  *     if(U_FAILURE(*pErrorCode)) {
   1423  *         return 0;
   1424  *     }
   1425  *
   1426  *     utf8Cnv=myGetCachedUTF8Converter(pErrorCode);
   1427  *     if(U_FAILURE(*pErrorCode)) {
   1428  *         return 0;
   1429  *     }
   1430  *
   1431  *     if(length<0) {
   1432  *         length=strlen(s);
   1433  *     }
   1434  *     target=u8;
   1435  *     ucnv_convertEx(utf8Cnv, cnv,
   1436  *                    &target, u8+capacity,
   1437  *                    &s, s+length,
   1438  *                    NULL, NULL, NULL, NULL,
   1439  *                    TRUE, TRUE,
   1440  *                    pErrorCode);
   1441  *
   1442  *     myReleaseCachedUTF8Converter(utf8Cnv);
   1443  *
   1444  *     // return the output string length, but without preflighting
   1445  *     return (int32_t)(target-u8);
   1446  * }
   1447  * \endcode
   1448  *
   1449  * @param targetCnv     Output converter, used to convert from the UTF-16 pivot
   1450  *                      to the target using ucnv_fromUnicode().
   1451  * @param sourceCnv     Input converter, used to convert from the source to
   1452  *                      the UTF-16 pivot using ucnv_toUnicode().
   1453  * @param target        I/O parameter, same as for ucnv_fromUChars().
   1454  *                      Input: *target points to the beginning of the target buffer.
   1455  *                      Output: *target points to the first unit after the last char written.
   1456  * @param targetLimit   Pointer to the first unit after the target buffer.
   1457  * @param source        I/O parameter, same as for ucnv_toUChars().
   1458  *                      Input: *source points to the beginning of the source buffer.
   1459  *                      Output: *source points to the first unit after the last char read.
   1460  * @param sourceLimit   Pointer to the first unit after the source buffer.
   1461  * @param pivotStart    Pointer to the UTF-16 pivot buffer. If pivotStart==NULL,
   1462  *                      then an internal buffer is used and the other pivot
   1463  *                      arguments are ignored and can be NULL as well.
   1464  * @param pivotSource   I/O parameter, same as source in ucnv_fromUChars() for
   1465  *                      conversion from the pivot buffer to the target buffer.
   1466  * @param pivotTarget   I/O parameter, same as target in ucnv_toUChars() for
   1467  *                      conversion from the source buffer to the pivot buffer.
   1468  *                      It must be pivotStart<=*pivotSource<=*pivotTarget<=pivotLimit
   1469  *                      and pivotStart<pivotLimit (unless pivotStart==NULL).
   1470  * @param pivotLimit    Pointer to the first unit after the pivot buffer.
   1471  * @param reset         If TRUE, then ucnv_resetToUnicode(sourceCnv) and
   1472  *                      ucnv_resetFromUnicode(targetCnv) are called, and the
   1473  *                      pivot pointers are reset (*pivotTarget=*pivotSource=pivotStart).
   1474  * @param flush         If true, indicates the end of the input.
   1475  *                      Passed directly to ucnv_toUnicode(), and carried over to
   1476  *                      ucnv_fromUnicode() when the source is empty as well.
   1477  * @param pErrorCode    ICU error code in/out parameter.
   1478  *                      Must fulfill U_SUCCESS before the function call.
   1479  *                      U_BUFFER_OVERFLOW_ERROR always refers to the target buffer
   1480  *                      because overflows into the pivot buffer are handled internally.
   1481  *                      Other conversion errors are from the source-to-pivot
   1482  *                      conversion if *pivotSource==pivotStart, otherwise from
   1483  *                      the pivot-to-target conversion.
   1484  *
   1485  * @see ucnv_convert
   1486  * @see ucnv_fromAlgorithmic
   1487  * @see ucnv_toAlgorithmic
   1488  * @see ucnv_fromUnicode
   1489  * @see ucnv_toUnicode
   1490  * @see ucnv_fromUChars
   1491  * @see ucnv_toUChars
   1492  * @stable ICU 2.6
   1493  */
   1494 U_STABLE void U_EXPORT2
   1495 ucnv_convertEx(UConverter *targetCnv, UConverter *sourceCnv,
   1496                char **target, const char *targetLimit,
   1497                const char **source, const char *sourceLimit,
   1498                UChar *pivotStart, UChar **pivotSource,
   1499                UChar **pivotTarget, const UChar *pivotLimit,
   1500                UBool reset, UBool flush,
   1501                UErrorCode *pErrorCode);
   1502 
   1503 /**
   1504  * Convert from one external charset to another.
   1505  * Internally, two converters are opened according to the name arguments,
   1506  * then the text is converted to and from the 16-bit Unicode "pivot"
   1507  * using ucnv_convertEx(), then the converters are closed again.
   1508  *
   1509  * This is a convenience function, not an efficient way to convert a lot of text:
   1510  * ucnv_convert()
   1511  * - takes charset names, not converter objects, so that
   1512  *   - two converters are opened for each call
   1513  *   - only single-string conversion is possible, not streaming operation
   1514  * - does not provide enough information to find out,
   1515  *   in case of failure, whether the toUnicode or
   1516  *   the fromUnicode conversion failed
   1517  * - allows NUL-terminated input
   1518  *   (only a single NUL byte, will not work for charsets with multi-byte NULs)
   1519  *   (if sourceLength==-1, see parameters)
   1520  * - terminate with a NUL on output
   1521  *   (only a single NUL byte, not useful for charsets with multi-byte NULs),
   1522  *   or set U_STRING_NOT_TERMINATED_WARNING if the output exactly fills
   1523  *   the target buffer
   1524  * - a pivot buffer is provided internally
   1525  *
   1526  * The function returns when one of the following is true:
   1527  * - the entire source text has been converted successfully to the target buffer
   1528  *   and either the target buffer is terminated with a single NUL byte
   1529  *   or the error code is set to U_STRING_NOT_TERMINATED_WARNING
   1530  * - a target buffer overflow occurred (U_BUFFER_OVERFLOW_ERROR)
   1531  *   and the full output string length is returned ("preflighting")
   1532  * - a conversion error occurred
   1533  *   (other U_FAILURE(), see description of pErrorCode)
   1534  *
   1535  * @param toConverterName   The name of the converter that is used to convert
   1536  *                          from the UTF-16 pivot buffer to the target.
   1537  * @param fromConverterName The name of the converter that is used to convert
   1538  *                          from the source to the UTF-16 pivot buffer.
   1539  * @param target            Pointer to the output buffer.
   1540  * @param targetCapacity    Capacity of the target, in bytes.
   1541  * @param source            Pointer to the input buffer.
   1542  * @param sourceLength      Length of the input text, in bytes, or -1 for NUL-terminated input.
   1543  * @param pErrorCode        ICU error code in/out parameter.
   1544  *                          Must fulfill U_SUCCESS before the function call.
   1545  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity
   1546  *         and a U_BUFFER_OVERFLOW_ERROR is set.
   1547  *
   1548  * @see ucnv_convertEx
   1549  * @see ucnv_fromAlgorithmic
   1550  * @see ucnv_toAlgorithmic
   1551  * @see ucnv_fromUnicode
   1552  * @see ucnv_toUnicode
   1553  * @see ucnv_fromUChars
   1554  * @see ucnv_toUChars
   1555  * @see ucnv_getNextUChar
   1556  * @stable ICU 2.0
   1557  */
   1558 U_STABLE int32_t U_EXPORT2
   1559 ucnv_convert(const char *toConverterName,
   1560              const char *fromConverterName,
   1561              char *target,
   1562              int32_t targetCapacity,
   1563              const char *source,
   1564              int32_t sourceLength,
   1565              UErrorCode *pErrorCode);
   1566 
   1567 /**
   1568  * Convert from one external charset to another.
   1569  * Internally, the text is converted to and from the 16-bit Unicode "pivot"
   1570  * using ucnv_convertEx(). ucnv_toAlgorithmic() works exactly like ucnv_convert()
   1571  * except that the two converters need not be looked up and opened completely.
   1572  *
   1573  * The source-to-pivot conversion uses the cnv converter parameter.
   1574  * The pivot-to-target conversion uses a purely algorithmic converter
   1575  * according to the specified type, e.g., UCNV_UTF8 for a UTF-8 converter.
   1576  *
   1577  * Internally, the algorithmic converter is opened and closed for each
   1578  * function call, which is more efficient than using the public ucnv_open()
   1579  * but somewhat less efficient than only resetting an existing converter
   1580  * and using ucnv_convertEx().
   1581  *
   1582  * This function is more convenient than ucnv_convertEx() for single-string
   1583  * conversions, especially when "preflighting" is desired (returning the length
   1584  * of the complete output even if it does not fit into the target buffer;
   1585  * see the User Guide Strings chapter). See ucnv_convert() for details.
   1586  *
   1587  * @param algorithmicType   UConverterType constant identifying the desired target
   1588  *                          charset as a purely algorithmic converter.
   1589  *                          Those are converters for Unicode charsets like
   1590  *                          UTF-8, BOCU-1, SCSU, UTF-7, IMAP-mailbox-name, etc.,
   1591  *                          as well as US-ASCII and ISO-8859-1.
   1592  * @param cnv               The converter that is used to convert
   1593  *                          from the source to the UTF-16 pivot buffer.
   1594  * @param target            Pointer to the output buffer.
   1595  * @param targetCapacity    Capacity of the target, in bytes.
   1596  * @param source            Pointer to the input buffer.
   1597  * @param sourceLength      Length of the input text, in bytes
   1598  * @param pErrorCode        ICU error code in/out parameter.
   1599  *                          Must fulfill U_SUCCESS before the function call.
   1600  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity
   1601  *         and a U_BUFFER_OVERFLOW_ERROR is set.
   1602  *
   1603  * @see ucnv_fromAlgorithmic
   1604  * @see ucnv_convert
   1605  * @see ucnv_convertEx
   1606  * @see ucnv_fromUnicode
   1607  * @see ucnv_toUnicode
   1608  * @see ucnv_fromUChars
   1609  * @see ucnv_toUChars
   1610  * @stable ICU 2.6
   1611  */
   1612 U_STABLE int32_t U_EXPORT2
   1613 ucnv_toAlgorithmic(UConverterType algorithmicType,
   1614                    UConverter *cnv,
   1615                    char *target, int32_t targetCapacity,
   1616                    const char *source, int32_t sourceLength,
   1617                    UErrorCode *pErrorCode);
   1618 
   1619 /**
   1620  * Convert from one external charset to another.
   1621  * Internally, the text is converted to and from the 16-bit Unicode "pivot"
   1622  * using ucnv_convertEx(). ucnv_fromAlgorithmic() works exactly like ucnv_convert()
   1623  * except that the two converters need not be looked up and opened completely.
   1624  *
   1625  * The source-to-pivot conversion uses a purely algorithmic converter
   1626  * according to the specified type, e.g., UCNV_UTF8 for a UTF-8 converter.
   1627  * The pivot-to-target conversion uses the cnv converter parameter.
   1628  *
   1629  * Internally, the algorithmic converter is opened and closed for each
   1630  * function call, which is more efficient than using the public ucnv_open()
   1631  * but somewhat less efficient than only resetting an existing converter
   1632  * and using ucnv_convertEx().
   1633  *
   1634  * This function is more convenient than ucnv_convertEx() for single-string
   1635  * conversions, especially when "preflighting" is desired (returning the length
   1636  * of the complete output even if it does not fit into the target buffer;
   1637  * see the User Guide Strings chapter). See ucnv_convert() for details.
   1638  *
   1639  * @param cnv               The converter that is used to convert
   1640  *                          from the UTF-16 pivot buffer to the target.
   1641  * @param algorithmicType   UConverterType constant identifying the desired source
   1642  *                          charset as a purely algorithmic converter.
   1643  *                          Those are converters for Unicode charsets like
   1644  *                          UTF-8, BOCU-1, SCSU, UTF-7, IMAP-mailbox-name, etc.,
   1645  *                          as well as US-ASCII and ISO-8859-1.
   1646  * @param target            Pointer to the output buffer.
   1647  * @param targetCapacity    Capacity of the target, in bytes.
   1648  * @param source            Pointer to the input buffer.
   1649  * @param sourceLength      Length of the input text, in bytes
   1650  * @param pErrorCode        ICU error code in/out parameter.
   1651  *                          Must fulfill U_SUCCESS before the function call.
   1652  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity
   1653  *         and a U_BUFFER_OVERFLOW_ERROR is set.
   1654  *
   1655  * @see ucnv_fromAlgorithmic
   1656  * @see ucnv_convert
   1657  * @see ucnv_convertEx
   1658  * @see ucnv_fromUnicode
   1659  * @see ucnv_toUnicode
   1660  * @see ucnv_fromUChars
   1661  * @see ucnv_toUChars
   1662  * @stable ICU 2.6
   1663  */
   1664 U_STABLE int32_t U_EXPORT2
   1665 ucnv_fromAlgorithmic(UConverter *cnv,
   1666                      UConverterType algorithmicType,
   1667                      char *target, int32_t targetCapacity,
   1668                      const char *source, int32_t sourceLength,
   1669                      UErrorCode *pErrorCode);
   1670 
   1671 /**
   1672  * Frees up memory occupied by unused, cached converter shared data.
   1673  *
   1674  * @return the number of cached converters successfully deleted
   1675  * @see ucnv_close
   1676  * @stable ICU 2.0
   1677  */
   1678 U_STABLE int32_t U_EXPORT2
   1679 ucnv_flushCache(void);
   1680 
   1681 /**
   1682  * Returns the number of available converters, as per the alias file.
   1683  *
   1684  * @return the number of available converters
   1685  * @see ucnv_getAvailableName
   1686  * @stable ICU 2.0
   1687  */
   1688 U_STABLE int32_t U_EXPORT2
   1689 ucnv_countAvailable(void);
   1690 
   1691 /**
   1692  * Gets the canonical converter name of the specified converter from a list of
   1693  * all available converters contaied in the alias file. All converters
   1694  * in this list can be opened.
   1695  *
   1696  * @param n the index to a converter available on the system (in the range <TT>[0..ucnv_countAvaiable()]</TT>)
   1697  * @return a pointer a string (library owned), or <TT>NULL</TT> if the index is out of bounds.
   1698  * @see ucnv_countAvailable
   1699  * @stable ICU 2.0
   1700  */
   1701 U_STABLE const char* U_EXPORT2
   1702 ucnv_getAvailableName(int32_t n);
   1703 
   1704 /**
   1705  * Returns a UEnumeration to enumerate all of the canonical converter
   1706  * names, as per the alias file, regardless of the ability to open each
   1707  * converter.
   1708  *
   1709  * @return A UEnumeration object for getting all the recognized canonical
   1710  *   converter names.
   1711  * @see ucnv_getAvailableName
   1712  * @see uenum_close
   1713  * @see uenum_next
   1714  * @stable ICU 2.4
   1715  */
   1716 U_STABLE UEnumeration * U_EXPORT2
   1717 ucnv_openAllNames(UErrorCode *pErrorCode);
   1718 
   1719 /**
   1720  * Gives the number of aliases for a given converter or alias name.
   1721  * If the alias is ambiguous, then the preferred converter is used
   1722  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.
   1723  * This method only enumerates the listed entries in the alias file.
   1724  * @param alias alias name
   1725  * @param pErrorCode error status
   1726  * @return number of names on alias list for given alias
   1727  * @stable ICU 2.0
   1728  */
   1729 U_STABLE uint16_t U_EXPORT2
   1730 ucnv_countAliases(const char *alias, UErrorCode *pErrorCode);
   1731 
   1732 /**
   1733  * Gives the name of the alias at given index of alias list.
   1734  * This method only enumerates the listed entries in the alias file.
   1735  * If the alias is ambiguous, then the preferred converter is used
   1736  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.
   1737  * @param alias alias name
   1738  * @param n index in alias list
   1739  * @param pErrorCode result of operation
   1740  * @return returns the name of the alias at given index
   1741  * @see ucnv_countAliases
   1742  * @stable ICU 2.0
   1743  */
   1744 U_STABLE const char * U_EXPORT2
   1745 ucnv_getAlias(const char *alias, uint16_t n, UErrorCode *pErrorCode);
   1746 
   1747 /**
   1748  * Fill-up the list of alias names for the given alias.
   1749  * This method only enumerates the listed entries in the alias file.
   1750  * If the alias is ambiguous, then the preferred converter is used
   1751  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.
   1752  * @param alias alias name
   1753  * @param aliases fill-in list, aliases is a pointer to an array of
   1754  *        <code>ucnv_countAliases()</code> string-pointers
   1755  *        (<code>const char *</code>) that will be filled in.
   1756  *        The strings themselves are owned by the library.
   1757  * @param pErrorCode result of operation
   1758  * @stable ICU 2.0
   1759  */
   1760 U_STABLE void U_EXPORT2
   1761 ucnv_getAliases(const char *alias, const char **aliases, UErrorCode *pErrorCode);
   1762 
   1763 /**
   1764  * Return a new UEnumeration object for enumerating all the
   1765  * alias names for a given converter that are recognized by a standard.
   1766  * This method only enumerates the listed entries in the alias file.
   1767  * The convrtrs.txt file can be modified to change the results of
   1768  * this function.
   1769  * The first result in this list is the same result given by
   1770  * <code>ucnv_getStandardName</code>, which is the default alias for
   1771  * the specified standard name. The returned object must be closed with
   1772  * <code>uenum_close</code> when you are done with the object.
   1773  *
   1774  * @param convName original converter name
   1775  * @param standard name of the standard governing the names; MIME and IANA
   1776  *      are such standards
   1777  * @param pErrorCode The error code
   1778  * @return A UEnumeration object for getting all aliases that are recognized
   1779  *      by a standard. If any of the parameters are invalid, NULL
   1780  *      is returned.
   1781  * @see ucnv_getStandardName
   1782  * @see uenum_close
   1783  * @see uenum_next
   1784  * @stable ICU 2.2
   1785  */
   1786 U_STABLE UEnumeration * U_EXPORT2
   1787 ucnv_openStandardNames(const char *convName,
   1788                        const char *standard,
   1789                        UErrorCode *pErrorCode);
   1790 
   1791 /**
   1792  * Gives the number of standards associated to converter names.
   1793  * @return number of standards
   1794  * @stable ICU 2.0
   1795  */
   1796 U_STABLE uint16_t U_EXPORT2
   1797 ucnv_countStandards(void);
   1798 
   1799 /**
   1800  * Gives the name of the standard at given index of standard list.
   1801  * @param n index in standard list
   1802  * @param pErrorCode result of operation
   1803  * @return returns the name of the standard at given index. Owned by the library.
   1804  * @stable ICU 2.0
   1805  */
   1806 U_STABLE const char * U_EXPORT2
   1807 ucnv_getStandard(uint16_t n, UErrorCode *pErrorCode);
   1808 
   1809 /**
   1810  * Returns a standard name for a given converter name.
   1811  * <p>
   1812  * Example alias table:<br>
   1813  * conv alias1 { STANDARD1 } alias2 { STANDARD1* }
   1814  * <p>
   1815  * Result of ucnv_getStandardName("conv", "STANDARD1") from example
   1816  * alias table:<br>
   1817  * <b>"alias2"</b>
   1818  *
   1819  * @param name original converter name
   1820  * @param standard name of the standard governing the names; MIME and IANA
   1821  *        are such standards
   1822  * @param pErrorCode result of operation
   1823  * @return returns the standard converter name;
   1824  *         if a standard converter name cannot be determined,
   1825  *         then <code>NULL</code> is returned. Owned by the library.
   1826  * @stable ICU 2.0
   1827  */
   1828 U_STABLE const char * U_EXPORT2
   1829 ucnv_getStandardName(const char *name, const char *standard, UErrorCode *pErrorCode);
   1830 
   1831 /**
   1832  * This function will return the internal canonical converter name of the
   1833  * tagged alias. This is the opposite of ucnv_openStandardNames, which
   1834  * returns the tagged alias given the canonical name.
   1835  * <p>
   1836  * Example alias table:<br>
   1837  * conv alias1 { STANDARD1 } alias2 { STANDARD1* }
   1838  * <p>
   1839  * Result of ucnv_getStandardName("alias1", "STANDARD1") from example
   1840  * alias table:<br>
   1841  * <b>"conv"</b>
   1842  *
   1843  * @return returns the canonical converter name;
   1844  *         if a standard or alias name cannot be determined,
   1845  *         then <code>NULL</code> is returned. The returned string is
   1846  *         owned by the library.
   1847  * @see ucnv_getStandardName
   1848  * @stable ICU 2.4
   1849  */
   1850 U_STABLE const char * U_EXPORT2
   1851 ucnv_getCanonicalName(const char *alias, const char *standard, UErrorCode *pErrorCode);
   1852 
   1853 /**
   1854  * Returns the current default converter name. If you want to open
   1855  * a default converter, you do not need to use this function.
   1856  * It is faster if you pass a NULL argument to ucnv_open the
   1857  * default converter.
   1858  *
   1859  * If U_CHARSET_IS_UTF8 is defined to 1 in utypes.h then this function
   1860  * always returns "UTF-8".
   1861  *
   1862  * @return returns the current default converter name.
   1863  *         Storage owned by the library
   1864  * @see ucnv_setDefaultName
   1865  * @stable ICU 2.0
   1866  */
   1867 U_STABLE const char * U_EXPORT2
   1868 ucnv_getDefaultName(void);
   1869 
   1870 #ifndef U_HIDE_SYSTEM_API
   1871 /**
   1872  * This function is not thread safe. DO NOT call this function when ANY ICU
   1873  * function is being used from more than one thread! This function sets the
   1874  * current default converter name. If this function needs to be called, it
   1875  * should be called during application initialization. Most of the time, the
   1876  * results from ucnv_getDefaultName() or ucnv_open with a NULL string argument
   1877  * is sufficient for your application.
   1878  *
   1879  * If U_CHARSET_IS_UTF8 is defined to 1 in utypes.h then this function
   1880  * does nothing.
   1881  *
   1882  * @param name the converter name to be the default (must be known by ICU).
   1883  * @see ucnv_getDefaultName
   1884  * @system
   1885  * @stable ICU 2.0
   1886  */
   1887 U_STABLE void U_EXPORT2
   1888 ucnv_setDefaultName(const char *name);
   1889 #endif  /* U_HIDE_SYSTEM_API */
   1890 
   1891 /**
   1892  * Fixes the backslash character mismapping.  For example, in SJIS, the backslash
   1893  * character in the ASCII portion is also used to represent the yen currency sign.
   1894  * When mapping from Unicode character 0x005C, it's unclear whether to map the
   1895  * character back to yen or backslash in SJIS.  This function will take the input
   1896  * buffer and replace all the yen sign characters with backslash.  This is necessary
   1897  * when the user tries to open a file with the input buffer on Windows.
   1898  * This function will test the converter to see whether such mapping is
   1899  * required.  You can sometimes avoid using this function by using the correct version
   1900  * of Shift-JIS.
   1901  *
   1902  * @param cnv The converter representing the target codepage.
   1903  * @param source the input buffer to be fixed
   1904  * @param sourceLen the length of the input buffer
   1905  * @see ucnv_isAmbiguous
   1906  * @stable ICU 2.0
   1907  */
   1908 U_STABLE void U_EXPORT2
   1909 ucnv_fixFileSeparator(const UConverter *cnv, UChar *source, int32_t sourceLen);
   1910 
   1911 /**
   1912  * Determines if the converter contains ambiguous mappings of the same
   1913  * character or not.
   1914  * @param cnv the converter to be tested
   1915  * @return TRUE if the converter contains ambiguous mapping of the same
   1916  * character, FALSE otherwise.
   1917  * @stable ICU 2.0
   1918  */
   1919 U_STABLE UBool U_EXPORT2
   1920 ucnv_isAmbiguous(const UConverter *cnv);
   1921 
   1922 /**
   1923  * Sets the converter to use fallback mappings or not.
   1924  * Regardless of this flag, the converter will always use
   1925  * fallbacks from Unicode Private Use code points, as well as
   1926  * reverse fallbacks (to Unicode).
   1927  * For details see ".ucm File Format"
   1928  * in the Conversion Data chapter of the ICU User Guide:
   1929  * http://www.icu-project.org/userguide/conversion-data.html#ucmformat
   1930  *
   1931  * @param cnv The converter to set the fallback mapping usage on.
   1932  * @param usesFallback TRUE if the user wants the converter to take advantage of the fallback
   1933  * mapping, FALSE otherwise.
   1934  * @stable ICU 2.0
   1935  * @see ucnv_usesFallback
   1936  */
   1937 U_STABLE void U_EXPORT2
   1938 ucnv_setFallback(UConverter *cnv, UBool usesFallback);
   1939 
   1940 /**
   1941  * Determines if the converter uses fallback mappings or not.
   1942  * This flag has restrictions, see ucnv_setFallback().
   1943  *
   1944  * @param cnv The converter to be tested
   1945  * @return TRUE if the converter uses fallback, FALSE otherwise.
   1946  * @stable ICU 2.0
   1947  * @see ucnv_setFallback
   1948  */
   1949 U_STABLE UBool U_EXPORT2
   1950 ucnv_usesFallback(const UConverter *cnv);
   1951 
   1952 /**
   1953  * Detects Unicode signature byte sequences at the start of the byte stream
   1954  * and returns the charset name of the indicated Unicode charset.
   1955  * NULL is returned when no Unicode signature is recognized.
   1956  * The number of bytes in the signature is output as well.
   1957  *
   1958  * The caller can ucnv_open() a converter using the charset name.
   1959  * The first code unit (UChar) from the start of the stream will be U+FEFF
   1960  * (the Unicode BOM/signature character) and can usually be ignored.
   1961  *
   1962  * For most Unicode charsets it is also possible to ignore the indicated
   1963  * number of initial stream bytes and start converting after them.
   1964  * However, there are stateful Unicode charsets (UTF-7 and BOCU-1) for which
   1965  * this will not work. Therefore, it is best to ignore the first output UChar
   1966  * instead of the input signature bytes.
   1967  * <p>
   1968  * Usage:
   1969  * \snippet samples/ucnv/convsamp.cpp ucnv_detectUnicodeSignature
   1970  *
   1971  * @param source            The source string in which the signature should be detected.
   1972  * @param sourceLength      Length of the input string, or -1 if terminated with a NUL byte.
   1973  * @param signatureLength   A pointer to int32_t to receive the number of bytes that make up the signature
   1974  *                          of the detected UTF. 0 if not detected.
   1975  *                          Can be a NULL pointer.
   1976  * @param pErrorCode        ICU error code in/out parameter.
   1977  *                          Must fulfill U_SUCCESS before the function call.
   1978  * @return The name of the encoding detected. NULL if encoding is not detected.
   1979  * @stable ICU 2.4
   1980  */
   1981 U_STABLE const char* U_EXPORT2
   1982 ucnv_detectUnicodeSignature(const char* source,
   1983                             int32_t sourceLength,
   1984                             int32_t *signatureLength,
   1985                             UErrorCode *pErrorCode);
   1986 
   1987 /**
   1988  * Returns the number of UChars held in the converter's internal state
   1989  * because more input is needed for completing the conversion. This function is
   1990  * useful for mapping semantics of ICU's converter interface to those of iconv,
   1991  * and this information is not needed for normal conversion.
   1992  * @param cnv       The converter in which the input is held
   1993  * @param status    ICU error code in/out parameter.
   1994  *                  Must fulfill U_SUCCESS before the function call.
   1995  * @return The number of UChars in the state. -1 if an error is encountered.
   1996  * @stable ICU 3.4
   1997  */
   1998 U_STABLE int32_t U_EXPORT2
   1999 ucnv_fromUCountPending(const UConverter* cnv, UErrorCode* status);
   2000 
   2001 /**
   2002  * Returns the number of chars held in the converter's internal state
   2003  * because more input is needed for completing the conversion. This function is
   2004  * useful for mapping semantics of ICU's converter interface to those of iconv,
   2005  * and this information is not needed for normal conversion.
   2006  * @param cnv       The converter in which the input is held as internal state
   2007  * @param status    ICU error code in/out parameter.
   2008  *                  Must fulfill U_SUCCESS before the function call.
   2009  * @return The number of chars in the state. -1 if an error is encountered.
   2010  * @stable ICU 3.4
   2011  */
   2012 U_STABLE int32_t U_EXPORT2
   2013 ucnv_toUCountPending(const UConverter* cnv, UErrorCode* status);
   2014 
   2015 /**
   2016  * Returns whether or not the charset of the converter has a fixed number of bytes
   2017  * per charset character.
   2018  * An example of this are converters that are of the type UCNV_SBCS or UCNV_DBCS.
   2019  * Another example is UTF-32 which is always 4 bytes per character.
   2020  * A Unicode code point may be represented by more than one UTF-8 or UTF-16 code unit
   2021  * but a UTF-32 converter encodes each code point with 4 bytes.
   2022  * Note: This method is not intended to be used to determine whether the charset has a
   2023  * fixed ratio of bytes to Unicode codes <i>units</i> for any particular Unicode encoding form.
   2024  * FALSE is returned with the UErrorCode if error occurs or cnv is NULL.
   2025  * @param cnv       The converter to be tested
   2026  * @param status    ICU error code in/out paramter
   2027  * @return TRUE if the converter is fixed-width
   2028  * @stable ICU 4.8
   2029  */
   2030 U_STABLE UBool U_EXPORT2
   2031 ucnv_isFixedWidth(UConverter *cnv, UErrorCode *status);
   2032 
   2033 #endif
   2034 
   2035 #endif
   2036 /*_UCNV*/
   2037