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 /*

 **********************************************************************

 *   Copyright (C) 1999-2013, International Business Machines

 *   Corporation and others.  All Rights Reserved.

 **********************************************************************

  *  ucnv.h:

  *  External APIs for the ICU's codeset conversion library

  *  Bertrand A. Damiba

  *

  * Modification History:

  *

  *   Date        Name        Description

  *   04/04/99    helena      Fixed internal header inclusion.

  *   05/11/00    helena      Added setFallback and usesFallback APIs.

  *   06/29/2000  helena      Major rewrite of the callback APIs.

  *   12/07/2000  srl         Update of documentation

  */

 /**

  * \file

  * \brief C API: Character conversion 

  *

  * <h2>Character Conversion C API</h2>

  *

  * <p>This API is used to convert codepage or character encoded data to and

  * from UTF-16. You can open a converter with {@link ucnv_open() }. With that

  * converter, you can get its properties, set options, convert your data and

  * close the converter.</p>

  *

  * <p>Since many software programs recogize different converter names for

  * different types of converters, there are other functions in this API to

  * iterate over the converter aliases. The functions {@link ucnv_getAvailableName() },

  * {@link ucnv_getAlias() } and {@link ucnv_getStandardName() } are some of the

  * more frequently used alias functions to get this information.</p>

  *

  * <p>When a converter encounters an illegal, irregular, invalid or unmappable character

  * its default behavior is to use a substitution character to replace the

  * bad byte sequence. This behavior can be changed by using {@link ucnv_setFromUCallBack() }

  * or {@link ucnv_setToUCallBack() } on the converter. The header ucnv_err.h defines

  * many other callback actions that can be used instead of a character substitution.</p>

  *

  * <p>More information about this API can be found in our 

  * <a href="http://icu-project.org/userguide/conversion.html">User's

  * Guide</a>.</p>

  */

 #ifndef UCNV_H

 #define UCNV_H

 #include "unicode/ucnv_err.h"

 #include "unicode/uenum.h"

 #include "unicode/localpointer.h"

 #ifndef __USET_H__

 /**

  * USet is the C API type for Unicode sets.

  * It is forward-declared here to avoid including the header file if related

  * conversion APIs are not used.

  * See unicode/uset.h

  *

  * @see ucnv_getUnicodeSet

  * @stable ICU 2.6

  */

 struct USet;

 /** @stable ICU 2.6 */

 typedef struct USet USet;

 #endif

 #if !UCONFIG_NO_CONVERSION

 U_CDECL_BEGIN

 /** Maximum length of a converter name including the terminating NULL @stable ICU 2.0 */

 #define UCNV_MAX_CONVERTER_NAME_LENGTH 60

 /** Maximum length of a converter name including path and terminating NULL @stable ICU 2.0 */

 #define UCNV_MAX_FULL_FILE_NAME_LENGTH (600+UCNV_MAX_CONVERTER_NAME_LENGTH)

 /** Shift in for EBDCDIC_STATEFUL and iso2022 states @stable ICU 2.0 */

 #define  UCNV_SI 0x0F

 /** Shift out for EBDCDIC_STATEFUL and iso2022 states @stable ICU 2.0 */

 #define  UCNV_SO 0x0E

 /**

  * Enum for specifying basic types of converters

  * @see ucnv_getType

  * @stable ICU 2.0

  */

 typedef enum {

     /** @stable ICU 2.0 */

     UCNV_UNSUPPORTED_CONVERTER = -1,

     /** @stable ICU 2.0 */

     UCNV_SBCS = 0,

     /** @stable ICU 2.0 */

     UCNV_DBCS = 1,

     /** @stable ICU 2.0 */

     UCNV_MBCS = 2,

     /** @stable ICU 2.0 */

     UCNV_LATIN_1 = 3,

     /** @stable ICU 2.0 */

     UCNV_UTF8 = 4,

     /** @stable ICU 2.0 */

     UCNV_UTF16_BigEndian = 5,

     /** @stable ICU 2.0 */

     UCNV_UTF16_LittleEndian = 6,

     /** @stable ICU 2.0 */

     UCNV_UTF32_BigEndian = 7,

     /** @stable ICU 2.0 */

     UCNV_UTF32_LittleEndian = 8,

     /** @stable ICU 2.0 */

     UCNV_EBCDIC_STATEFUL = 9,

     /** @stable ICU 2.0 */

     UCNV_ISO_2022 = 10,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_1 = 11,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_2, 

     /** @stable ICU 2.0 */

     UCNV_LMBCS_3,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_4,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_5,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_6,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_8,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_11,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_16,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_17,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_18,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_19,

     /** @stable ICU 2.0 */

     UCNV_LMBCS_LAST = UCNV_LMBCS_19,

     /** @stable ICU 2.0 */

     UCNV_HZ,

     /** @stable ICU 2.0 */

     UCNV_SCSU,

     /** @stable ICU 2.0 */

     UCNV_ISCII,

     /** @stable ICU 2.0 */

     UCNV_US_ASCII,

     /** @stable ICU 2.0 */

     UCNV_UTF7,

     /** @stable ICU 2.2 */

     UCNV_BOCU1,

     /** @stable ICU 2.2 */

     UCNV_UTF16,

     /** @stable ICU 2.2 */

     UCNV_UTF32,

     /** @stable ICU 2.2 */

     UCNV_CESU8,

     /** @stable ICU 2.4 */

     UCNV_IMAP_MAILBOX,

     /** @stable ICU 4.8 */

     UCNV_COMPOUND_TEXT,

     /* Number of converter types for which we have conversion routines. */

     UCNV_NUMBER_OF_SUPPORTED_CONVERTER_TYPES

 } UConverterType;

 /**

  * Enum for specifying which platform a converter ID refers to.

  * The use of platform/CCSID is not recommended. See ucnv_openCCSID().

  *

  * @see ucnv_getPlatform

  * @see ucnv_openCCSID

  * @see ucnv_getCCSID

  * @stable ICU 2.0

  */

 typedef enum {

     UCNV_UNKNOWN = -1,

     UCNV_IBM = 0

 } UConverterPlatform;

 /**

  * Function pointer for error callback in the codepage to unicode direction.

  * Called when an error has occured in conversion to unicode, or on open/close of the callback (see reason).

  * @param context Pointer to the callback's private data

  * @param args Information about the conversion in progress

  * @param codeUnits Points to 'length' bytes of the concerned codepage sequence

  * @param length Size (in bytes) of the concerned codepage sequence

  * @param reason Defines the reason the callback was invoked

  * @param pErrorCode    ICU error code in/out parameter.

  *                      For converter callback functions, set to a conversion error

  *                      before the call, and the callback may reset it to U_ZERO_ERROR.

  * @see ucnv_setToUCallBack

  * @see UConverterToUnicodeArgs

  * @stable ICU 2.0

  */

 typedef void (U_EXPORT2 *UConverterToUCallback) (

                   const void* context,

                   UConverterToUnicodeArgs *args,

                   const char *codeUnits,

                   int32_t length,

                   UConverterCallbackReason reason,

                   UErrorCode *pErrorCode);

 /**

  * Function pointer for error callback in the unicode to codepage direction.

  * Called when an error has occured in conversion from unicode, or on open/close of the callback (see reason).

  * @param context Pointer to the callback's private data

  * @param args Information about the conversion in progress

  * @param codeUnits Points to 'length' UChars of the concerned Unicode sequence

  * @param length Size (in bytes) of the concerned codepage sequence

  * @param codePoint Single UChar32 (UTF-32) containing the concerend Unicode codepoint.

  * @param reason Defines the reason the callback was invoked

  * @param pErrorCode    ICU error code in/out parameter.

  *                      For converter callback functions, set to a conversion error

  *                      before the call, and the callback may reset it to U_ZERO_ERROR.

  * @see ucnv_setFromUCallBack

  * @stable ICU 2.0

  */

 typedef void (U_EXPORT2 *UConverterFromUCallback) (

                     const void* context,

                     UConverterFromUnicodeArgs *args,

                     const UChar* codeUnits,

                     int32_t length,

                     UChar32 codePoint,

                     UConverterCallbackReason reason,

                     UErrorCode *pErrorCode);

 U_CDECL_END

 /**

  * Character that separates converter names from options and options from each other.

  * @see ucnv_open

  * @stable ICU 2.0

  */

 #define UCNV_OPTION_SEP_CHAR ','

 /**

  * String version of UCNV_OPTION_SEP_CHAR. 

  * @see ucnv_open

  * @stable ICU 2.0

  */

 #define UCNV_OPTION_SEP_STRING ","

 /**

  * Character that separates a converter option from its value.

  * @see ucnv_open

  * @stable ICU 2.0

  */

 #define UCNV_VALUE_SEP_CHAR '='

 /**

  * String version of UCNV_VALUE_SEP_CHAR. 

  * @see ucnv_open

  * @stable ICU 2.0

  */

 #define UCNV_VALUE_SEP_STRING "="

 /**

  * Converter option for specifying a locale.

  * For example, ucnv_open("SCSU,locale=ja", &errorCode);

  * See convrtrs.txt.

  *

  * @see ucnv_open

  * @stable ICU 2.0

  */

 #define UCNV_LOCALE_OPTION_STRING ",locale="

 /**

  * Converter option for specifying a version selector (0..9) for some converters.

  * For example, 

  * \code

  *   ucnv_open("UTF-7,version=1", &errorCode);

  * \endcode

  * See convrtrs.txt.

  *

  * @see ucnv_open

  * @stable ICU 2.4

  */

 #define UCNV_VERSION_OPTION_STRING ",version="

 /**

  * Converter option for EBCDIC SBCS or mixed-SBCS/DBCS (stateful) codepages.

  * Swaps Unicode mappings for EBCDIC LF and NL codes, as used on

  * S/390 (z/OS) Unix System Services (Open Edition).

  * For example, ucnv_open("ibm-1047,swaplfnl", &errorCode);

  * See convrtrs.txt.

  *

  * @see ucnv_open

  * @stable ICU 2.4

  */

 #define UCNV_SWAP_LFNL_OPTION_STRING ",swaplfnl"

 /**

  * Do a fuzzy compare of two converter/alias names.

  * The comparison is case-insensitive, ignores leading zeroes if they are not

  * followed by further digits, and ignores all but letters and digits.

  * Thus the strings "UTF-8", "utf_8", "u*T@f08" and "Utf 8" are exactly equivalent.

  * See section 1.4, Charset Alias Matching in Unicode Technical Standard #22

  * at http://www.unicode.org/reports/tr22/

  *

  * @param name1 a converter name or alias, zero-terminated

  * @param name2 a converter name or alias, zero-terminated

  * @return 0 if the names match, or a negative value if the name1

  * lexically precedes name2, or a positive value if the name1

  * lexically follows name2.

  * @stable ICU 2.0

  */

 U_STABLE int U_EXPORT2

 ucnv_compareNames(const char *name1, const char *name2);

 /**

  * Creates a UConverter object with the name of a coded character set specified as a C string.

  * The actual name will be resolved with the alias file

  * using a case-insensitive string comparison that ignores

  * leading zeroes and all non-alphanumeric characters.

  * E.g., the names "UTF8", "utf-8", "u*T@f08" and "Utf 8" are all equivalent.

  * (See also ucnv_compareNames().)

  * If <code>NULL</code> is passed for the converter name, it will create one with the

  * getDefaultName return value.

  *

  * <p>A converter name for ICU 1.5 and above may contain options

  * like a locale specification to control the specific behavior of

  * the newly instantiated converter.

  * The meaning of the options depends on the particular converter.

  * If an option is not defined for or recognized by a given converter, then it is ignored.</p>

  *

  * <p>Options are appended to the converter name string, with a

  * <code>UCNV_OPTION_SEP_CHAR</code> between the name and the first option and

  * also between adjacent options.</p>

  *

  * <p>If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.</p>

  *

  * <p>The conversion behavior and names can vary between platforms. ICU may

  * convert some characters differently from other platforms. Details on this topic

  * are in the <a href="http://icu-project.org/userguide/conversion.html">User's

  * Guide</a>. Aliases starting with a "cp" prefix have no specific meaning

  * other than its an alias starting with the letters "cp". Please do not

  * associate any meaning to these aliases.</p>

  *

  * \snippet samples/ucnv/convsamp.cpp ucnv_open

  *

  * @param converterName Name of the coded character set table.

  *          This may have options appended to the string.

  *          IANA alias character set names, IBM CCSIDs starting with "ibm-",

  *          Windows codepage numbers starting with "windows-" are frequently

  *          used for this parameter. See ucnv_getAvailableName and

  *          ucnv_getAlias for a complete list that is available.

  *          If this parameter is NULL, the default converter will be used.

  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>

  * @return the created Unicode converter object, or <TT>NULL</TT> if an error occured

  * @see ucnv_openU

  * @see ucnv_openCCSID

  * @see ucnv_getAvailableName

  * @see ucnv_getAlias

  * @see ucnv_getDefaultName

  * @see ucnv_close

  * @see ucnv_compareNames

  * @stable ICU 2.0

  */

 U_STABLE UConverter* U_EXPORT2 

 ucnv_open(const char *converterName, UErrorCode *err);

 /**

  * Creates a Unicode converter with the names specified as unicode string. 

  * The name should be limited to the ASCII-7 alphanumerics range.

  * The actual name will be resolved with the alias file

  * using a case-insensitive string comparison that ignores

  * leading zeroes and all non-alphanumeric characters.

  * E.g., the names "UTF8", "utf-8", "u*T@f08" and "Utf 8" are all equivalent.

  * (See also ucnv_compareNames().)

  * If <TT>NULL</TT> is passed for the converter name, it will create 

  * one with the ucnv_getDefaultName() return value.

  * If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.

  *

  * <p>See ucnv_open for the complete details</p>

  * @param name Name of the UConverter table in a zero terminated 

  *        Unicode string

  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR, 

  *        U_FILE_ACCESS_ERROR</TT>

  * @return the created Unicode converter object, or <TT>NULL</TT> if an 

  *        error occured

  * @see ucnv_open

  * @see ucnv_openCCSID

  * @see ucnv_close

  * @see ucnv_compareNames

  * @stable ICU 2.0

  */

 U_STABLE UConverter* U_EXPORT2 

 ucnv_openU(const UChar *name,

            UErrorCode *err);

 /**

  * Creates a UConverter object from a CCSID number and platform pair.

  * Note that the usefulness of this function is limited to platforms with numeric

  * encoding IDs. Only IBM and Microsoft platforms use numeric (16-bit) identifiers for

  * encodings.

  *

  * In addition, IBM CCSIDs and Unicode conversion tables are not 1:1 related.

  * For many IBM CCSIDs there are multiple (up to six) Unicode conversion tables, and

  * for some Unicode conversion tables there are multiple CCSIDs.

  * Some "alternate" Unicode conversion tables are provided by the

  * IBM CDRA conversion table registry.

  * The most prominent example of a systematic modification of conversion tables that is

  * not provided in the form of conversion table files in the repository is

  * that S/390 Unix System Services swaps the codes for Line Feed and New Line in all

  * EBCDIC codepages, which requires such a swap in the Unicode conversion tables as well.

  *

  * Only IBM default conversion tables are accessible with ucnv_openCCSID().

  * ucnv_getCCSID() will return the same CCSID for all conversion tables that are associated

  * with that CCSID.

  *

  * Currently, the only "platform" supported in the ICU converter API is UCNV_IBM.

  *

  * In summary, the use of CCSIDs and the associated API functions is not recommended.

  *

  * In order to open a converter with the default IBM CDRA Unicode conversion table,

  * you can use this function or use the prefix "ibm-":

  * \code

  *     char name[20];

  *     sprintf(name, "ibm-%hu", ccsid);

  *     cnv=ucnv_open(name, &errorCode);

  * \endcode

  *

  * In order to open a converter with the IBM S/390 Unix System Services variant

  * of a Unicode/EBCDIC conversion table,

  * you can use the prefix "ibm-" together with the option string UCNV_SWAP_LFNL_OPTION_STRING:

  * \code

  *     char name[20];

  *     sprintf(name, "ibm-%hu" UCNV_SWAP_LFNL_OPTION_STRING, ccsid);

  *     cnv=ucnv_open(name, &errorCode);

  * \endcode

  *

  * In order to open a converter from a Microsoft codepage number, use the prefix "cp":

  * \code

  *     char name[20];

  *     sprintf(name, "cp%hu", codepageID);

  *     cnv=ucnv_open(name, &errorCode);

  * \endcode

  *

  * If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.

  *

  * @param codepage codepage number to create

  * @param platform the platform in which the codepage number exists

  * @param err error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>

  * @return the created Unicode converter object, or <TT>NULL</TT> if an error

  *   occured.

  * @see ucnv_open

  * @see ucnv_openU

  * @see ucnv_close

  * @see ucnv_getCCSID

  * @see ucnv_getPlatform

  * @see UConverterPlatform

  * @stable ICU 2.0

  */

 U_STABLE UConverter* U_EXPORT2

 ucnv_openCCSID(int32_t codepage,

                UConverterPlatform platform,

                UErrorCode * err);

 /**

  * <p>Creates a UConverter object specified from a packageName and a converterName.</p>

  * 

  * <p>The packageName and converterName must point to an ICU udata object, as defined by

  *   <code> udata_open( packageName, "cnv", converterName, err) </code> or equivalent.

  * Typically, packageName will refer to a (.dat) file, or to a package registered with

  * udata_setAppData(). Using a full file or directory pathname for packageName is deprecated.</p>

  * 

  * <p>The name will NOT be looked up in the alias mechanism, nor will the converter be

  * stored in the converter cache or the alias table. The only way to open further converters

  * is call this function multiple times, or use the ucnv_safeClone() function to clone a 

  * 'master' converter.</p>

  *

  * <p>A future version of ICU may add alias table lookups and/or caching

  * to this function.</p>

  * 

  * <p>Example Use:

  *      <code>cnv = ucnv_openPackage("myapp", "myconverter", &err);</code>

  * </p>

  *

  * @param packageName name of the package (equivalent to 'path' in udata_open() call)

  * @param converterName name of the data item to be used, without suffix.

  * @param err outgoing error status <TT>U_MEMORY_ALLOCATION_ERROR, U_FILE_ACCESS_ERROR</TT>

  * @return the created Unicode converter object, or <TT>NULL</TT> if an error occured

  * @see udata_open

  * @see ucnv_open

  * @see ucnv_safeClone

  * @see ucnv_close

  * @stable ICU 2.2

  */

 U_STABLE UConverter* U_EXPORT2 

 ucnv_openPackage(const char *packageName, const char *converterName, UErrorCode *err);

 /**

  * Thread safe converter cloning operation.

  * For most efficient operation, pass in a stackBuffer (and a *pBufferSize)

  * with at least U_CNV_SAFECLONE_BUFFERSIZE bytes of space.

  * If the buffer size is sufficient, then the clone will use the stack buffer;

  * otherwise, it will be allocated, and *pBufferSize will indicate

  * the actual size. (This should not occur with U_CNV_SAFECLONE_BUFFERSIZE.)

  *

  * You must ucnv_close() the clone in any case.

  *

  * If *pBufferSize==0, (regardless of whether stackBuffer==NULL or not)

  * then *pBufferSize will be changed to a sufficient size

  * for cloning this converter,

  * without actually cloning the converter ("pure pre-flighting").

  *

  * If *pBufferSize is greater than zero but not large enough for a stack-based

  * clone, then the converter is cloned using newly allocated memory

  * and *pBufferSize is changed to the necessary size.

  *

  * If the converter clone fits into the stack buffer but the stack buffer is not

  * sufficiently aligned for the clone, then the clone will use an

  * adjusted pointer and use an accordingly smaller buffer size.

  *

  * @param cnv converter to be cloned

  * @param stackBuffer <em>Deprecated functionality as of ICU 52, use NULL.</em><br>

  *  user allocated space for the new clone. If NULL new memory will be allocated. 

  *  If buffer is not large enough, new memory will be allocated.

  *  Clients can use the U_CNV_SAFECLONE_BUFFERSIZE. This will probably be enough to avoid memory allocations.

  * @param pBufferSize <em>Deprecated functionality as of ICU 52, use NULL or 1.</em><br>

  *  pointer to size of allocated space.

  * @param status to indicate whether the operation went on smoothly or there were errors

  *  An informational status value, U_SAFECLONE_ALLOCATED_WARNING,

  *  is used if any allocations were necessary.

  *  However, it is better to check if *pBufferSize grew for checking for

  *  allocations because warning codes can be overridden by subsequent

  *  function calls.

  * @return pointer to the new clone

  * @stable ICU 2.0

  */

 U_STABLE UConverter * U_EXPORT2 

 ucnv_safeClone(const UConverter *cnv, 

                void             *stackBuffer,

                int32_t          *pBufferSize, 

                UErrorCode       *status);

 #ifndef U_HIDE_DEPRECATED_API

 /**

  * \def U_CNV_SAFECLONE_BUFFERSIZE

  * Definition of a buffer size that is designed to be large enough for

  * converters to be cloned with ucnv_safeClone().

  * @deprecated ICU 52. Do not rely on ucnv_safeClone() cloning into any provided buffer.

  */

 #define U_CNV_SAFECLONE_BUFFERSIZE  1024

 #endif /* U_HIDE_DEPRECATED_API */

 /**

  * Deletes the unicode converter and releases resources associated

  * with just this instance.

  * Does not free up shared converter tables.

  *

  * @param converter the converter object to be deleted

  * @see ucnv_open

  * @see ucnv_openU

  * @see ucnv_openCCSID

  * @stable ICU 2.0

  */

 U_STABLE void  U_EXPORT2

 ucnv_close(UConverter * converter);

 #if U_SHOW_CPLUSPLUS_API

 U_NAMESPACE_BEGIN

 /**

  * \class LocalUConverterPointer

  * "Smart pointer" class, closes a UConverter via ucnv_close().

  * For most methods see the LocalPointerBase base class.

  *

  * @see LocalPointerBase

  * @see LocalPointer

  * @stable ICU 4.4

  */

 U_DEFINE_LOCAL_OPEN_POINTER(LocalUConverterPointer, UConverter, ucnv_close);

 U_NAMESPACE_END

 #endif

 /**

  * Fills in the output parameter, subChars, with the substitution characters

  * as multiple bytes.

  * If ucnv_setSubstString() set a Unicode string because the converter is

  * stateful, then subChars will be an empty string.

  *

  * @param converter the Unicode converter

  * @param subChars the subsitution characters

  * @param len on input the capacity of subChars, on output the number 

  * of bytes copied to it

  * @param  err the outgoing error status code.

  * If the substitution character array is too small, an

  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.

  * @see ucnv_setSubstString

  * @see ucnv_setSubstChars

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getSubstChars(const UConverter *converter,

                    char *subChars,

                    int8_t *len,

                    UErrorCode *err);

 /**

  * Sets the substitution chars when converting from unicode to a codepage. The

  * substitution is specified as a string of 1-4 bytes, and may contain

  * <TT>NULL</TT> bytes.

  * The subChars must represent a single character. The caller needs to know the

  * byte sequence of a valid character in the converter's charset.

  * For some converters, for example some ISO 2022 variants, only single-byte

  * substitution characters may be supported.

  * The newer ucnv_setSubstString() function relaxes these limitations.

  *

  * @param converter the Unicode converter

  * @param subChars the substitution character byte sequence we want set

  * @param len the number of bytes in subChars

  * @param err the error status code.  <TT>U_INDEX_OUTOFBOUNDS_ERROR </TT> if

  * len is bigger than the maximum number of bytes allowed in subchars

  * @see ucnv_setSubstString

  * @see ucnv_getSubstChars

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_setSubstChars(UConverter *converter,

                    const char *subChars,

                    int8_t len,

                    UErrorCode *err);

 /**

  * Set a substitution string for converting from Unicode to a charset.

  * The caller need not know the charset byte sequence for each charset.

  *

  * Unlike ucnv_setSubstChars() which is designed to set a charset byte sequence

  * for a single character, this function takes a Unicode string with

  * zero, one or more characters, and immediately verifies that the string can be

  * converted to the charset.

  * If not, or if the result is too long (more than 32 bytes as of ICU 3.6),

  * then the function returns with an error accordingly.

  *

  * Also unlike ucnv_setSubstChars(), this function works for stateful charsets

  * by converting on the fly at the point of substitution rather than setting

  * a fixed byte sequence.

  *

  * @param cnv The UConverter object.

  * @param s The Unicode string.

  * @param length The number of UChars in s, or -1 for a NUL-terminated string.

  * @param err Pointer to a standard ICU error code. Its input value must

  *            pass the U_SUCCESS() test, or else the function returns

  *            immediately. Check for U_FAILURE() on output or use with

  *            function chaining. (See User Guide for details.)

  *

  * @see ucnv_setSubstChars

  * @see ucnv_getSubstChars

  * @stable ICU 3.6

  */

 U_STABLE void U_EXPORT2

 ucnv_setSubstString(UConverter *cnv,

                     const UChar *s,

                     int32_t length,

                     UErrorCode *err);

 /**

  * Fills in the output parameter, errBytes, with the error characters from the

  * last failing conversion.

  *

  * @param converter the Unicode converter

  * @param errBytes the codepage bytes which were in error

  * @param len on input the capacity of errBytes, on output the number of

  *  bytes which were copied to it

  * @param err the error status code.

  * If the substitution character array is too small, an

  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getInvalidChars(const UConverter *converter,

                      char *errBytes,

                      int8_t *len,

                      UErrorCode *err);

 /**

  * Fills in the output parameter, errChars, with the error characters from the

  * last failing conversion.

  *

  * @param converter the Unicode converter

  * @param errUChars the UChars which were in error

  * @param len on input the capacity of errUChars, on output the number of 

  *  UChars which were copied to it

  * @param err the error status code.

  * If the substitution character array is too small, an

  * <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT> will be returned.

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getInvalidUChars(const UConverter *converter,

                       UChar *errUChars,

                       int8_t *len,

                       UErrorCode *err);

 /**

  * Resets the state of a converter to the default state. This is used

  * in the case of an error, to restart a conversion from a known default state.

  * It will also empty the internal output buffers.

  * @param converter the Unicode converter

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_reset(UConverter *converter);

 /**

  * Resets the to-Unicode part of a converter state to the default state.

  * This is used in the case of an error to restart a conversion to

  * Unicode to a known default state. It will also empty the internal

  * output buffers used for the conversion to Unicode codepoints.

  * @param converter the Unicode converter

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2 

 ucnv_resetToUnicode(UConverter *converter);

 /**

  * Resets the from-Unicode part of a converter state to the default state.

  * This is used in the case of an error to restart a conversion from

  * Unicode to a known default state. It will also empty the internal output

  * buffers used for the conversion from Unicode codepoints.

  * @param converter the Unicode converter

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2 

 ucnv_resetFromUnicode(UConverter *converter);

 /**

  * Returns the maximum number of bytes that are output per UChar in conversion

  * from Unicode using this converter.

  * The returned number can be used with UCNV_GET_MAX_BYTES_FOR_STRING

  * to calculate the size of a target buffer for conversion from Unicode.

  *

  * Note: Before ICU 2.8, this function did not return reliable numbers for

  * some stateful converters (EBCDIC_STATEFUL, ISO-2022) and LMBCS.

  *

  * This number may not be the same as the maximum number of bytes per

  * "conversion unit". In other words, it may not be the intuitively expected

  * number of bytes per character that would be published for a charset,

  * and may not fulfill any other purpose than the allocation of an output

  * buffer of guaranteed sufficient size for a given input length and converter.

  *

  * Examples for special cases that are taken into account:

  * - Supplementary code points may convert to more bytes than BMP code points.

  *   This function returns bytes per UChar (UTF-16 code unit), not per

  *   Unicode code point, for efficient buffer allocation.

  * - State-shifting output (SI/SO, escapes, etc.) from stateful converters.

  * - When m input UChars are converted to n output bytes, then the maximum m/n

  *   is taken into account.

  *

  * The number returned here does not take into account

  * (see UCNV_GET_MAX_BYTES_FOR_STRING):

  * - callbacks which output more than one charset character sequence per call,

  *   like escape callbacks

  * - initial and final non-character bytes that are output by some converters

  *   (automatic BOMs, initial escape sequence, final SI, etc.)

  *

  * Examples for returned values:

  * - SBCS charsets: 1

  * - Shift-JIS: 2

  * - UTF-16: 2 (2 per BMP, 4 per surrogate _pair_, BOM not counted)

  * - UTF-8: 3 (3 per BMP, 4 per surrogate _pair_)

  * - EBCDIC_STATEFUL (EBCDIC mixed SBCS/DBCS): 3 (SO + DBCS)

  * - ISO-2022: 3 (always outputs UTF-8)

  * - ISO-2022-JP: 6 (4-byte escape sequences + DBCS)

  * - ISO-2022-CN: 8 (4-byte designator sequences + 2-byte SS2/SS3 + DBCS)

  *

  * @param converter The Unicode converter.

  * @return The maximum number of bytes per UChar that are output by ucnv_fromUnicode(),

  *         to be used together with UCNV_GET_MAX_BYTES_FOR_STRING for buffer allocation.

  *

  * @see UCNV_GET_MAX_BYTES_FOR_STRING

  * @see ucnv_getMinCharSize

  * @stable ICU 2.0

  */

 U_STABLE int8_t U_EXPORT2

 ucnv_getMaxCharSize(const UConverter *converter);

 /**

  * Calculates the size of a buffer for conversion from Unicode to a charset.

  * The calculated size is guaranteed to be sufficient for this conversion.

  *

  * It takes into account initial and final non-character bytes that are output

  * by some converters.

  * It does not take into account callbacks which output more than one charset

  * character sequence per call, like escape callbacks.

  * The default (substitution) callback only outputs one charset character sequence.

  *

  * @param length Number of UChars to be converted.

  * @param maxCharSize Return value from ucnv_getMaxCharSize() for the converter

  *                    that will be used.

  * @return Size of a buffer that will be large enough to hold the output bytes of

  *         converting length UChars with the converter that returned the maxCharSize.

  *

  * @see ucnv_getMaxCharSize

  * @stable ICU 2.8

  */

 #define UCNV_GET_MAX_BYTES_FOR_STRING(length, maxCharSize) \

      (((int32_t)(length)+10)*(int32_t)(maxCharSize))

 /**

  * Returns the minimum byte length for characters in this codepage. 

  * This is usually either 1 or 2.

  * @param converter the Unicode converter

  * @return the minimum number of bytes allowed by this particular converter

  * @see ucnv_getMaxCharSize

  * @stable ICU 2.0

  */

 U_STABLE int8_t U_EXPORT2

 ucnv_getMinCharSize(const UConverter *converter);

 /**

  * Returns the display name of the converter passed in based on the Locale 

  * passed in. If the locale contains no display name, the internal ASCII

  * name will be filled in.

  *

  * @param converter the Unicode converter.

  * @param displayLocale is the specific Locale we want to localised for

  * @param displayName user provided buffer to be filled in

  * @param displayNameCapacity size of displayName Buffer

  * @param err error status code

  * @return displayNameLength number of UChar needed in displayName

  * @see ucnv_getName

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_getDisplayName(const UConverter *converter,

                     const char *displayLocale,

                     UChar *displayName,

                     int32_t displayNameCapacity,

                     UErrorCode *err);

 /**

  * Gets the internal, canonical name of the converter (zero-terminated).

  * The lifetime of the returned string will be that of the converter 

  * passed to this function.

  * @param converter the Unicode converter

  * @param err UErrorCode status

  * @return the internal name of the converter

  * @see ucnv_getDisplayName

  * @stable ICU 2.0

  */

 U_STABLE const char * U_EXPORT2 

 ucnv_getName(const UConverter *converter, UErrorCode *err);

 /**

  * Gets a codepage number associated with the converter. This is not guaranteed

  * to be the one used to create the converter. Some converters do not represent

  * platform registered codepages and return zero for the codepage number.

  * The error code fill-in parameter indicates if the codepage number

  * is available.

  * Does not check if the converter is <TT>NULL</TT> or if converter's data

  * table is <TT>NULL</TT>.

  *

  * Important: The use of CCSIDs is not recommended because it is limited

  * to only two platforms in principle and only one (UCNV_IBM) in the current

  * ICU converter API.

  * Also, CCSIDs are insufficient to identify IBM Unicode conversion tables precisely.

  * For more details see ucnv_openCCSID().

  *

  * @param converter the Unicode converter

  * @param err the error status code.

  * @return If any error occurrs, -1 will be returned otherwise, the codepage number

  * will be returned

  * @see ucnv_openCCSID

  * @see ucnv_getPlatform

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_getCCSID(const UConverter *converter,

               UErrorCode *err);

 /**

  * Gets a codepage platform associated with the converter. Currently, 

  * only <TT>UCNV_IBM</TT> will be returned.

  * Does not test if the converter is <TT>NULL</TT> or if converter's data 

  * table is <TT>NULL</TT>. 

  * @param converter the Unicode converter

  * @param err the error status code.

  * @return The codepage platform

  * @stable ICU 2.0

  */

 U_STABLE UConverterPlatform U_EXPORT2

 ucnv_getPlatform(const UConverter *converter,

                  UErrorCode *err);

 /**

  * Gets the type of the converter

  * e.g. SBCS, MBCS, DBCS, UTF8, UTF16_BE, UTF16_LE, ISO_2022, 

  * EBCDIC_STATEFUL, LATIN_1

  * @param converter a valid, opened converter

  * @return the type of the converter

  * @stable ICU 2.0

  */

 U_STABLE UConverterType U_EXPORT2

 ucnv_getType(const UConverter * converter);

 /**

  * Gets the "starter" (lead) bytes for converters of type MBCS.

  * Will fill in an <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> if converter passed in

  * is not MBCS. Fills in an array of type UBool, with the value of the byte 

  * as offset to the array. For example, if (starters[0x20] == TRUE) at return,

  * it means that the byte 0x20 is a starter byte in this converter.

  * Context pointers are always owned by the caller.

  * 

  * @param converter a valid, opened converter of type MBCS

  * @param starters an array of size 256 to be filled in

  * @param err error status, <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> if the 

  * converter is not a type which can return starters.

  * @see ucnv_getType

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getStarters(const UConverter* converter, 

                  UBool starters[256],

                  UErrorCode* err);

 /**

  * Selectors for Unicode sets that can be returned by ucnv_getUnicodeSet().

  * @see ucnv_getUnicodeSet

  * @stable ICU 2.6

  */

 typedef enum UConverterUnicodeSet {

     /** Select the set of roundtrippable Unicode code points. @stable ICU 2.6 */

     UCNV_ROUNDTRIP_SET,

     /** Select the set of Unicode code points with roundtrip or fallback mappings. @stable ICU 4.0 */

     UCNV_ROUNDTRIP_AND_FALLBACK_SET,

     /** Number of UConverterUnicodeSet selectors. @stable ICU 2.6 */

     UCNV_SET_COUNT

 } UConverterUnicodeSet;

 /**

  * Returns the set of Unicode code points that can be converted by an ICU converter.

  *

  * Returns one of several kinds of set:

  *

  * 1. UCNV_ROUNDTRIP_SET

  *

  * The set of all Unicode code points that can be roundtrip-converted

  * (converted without any data loss) with the converter (ucnv_fromUnicode()).

  * This set will not include code points that have fallback mappings

  * or are only the result of reverse fallback mappings.

  * This set will also not include PUA code points with fallbacks, although

  * ucnv_fromUnicode() will always uses those mappings despite ucnv_setFallback().

  * See UTR #22 "Character Mapping Markup Language"

  * at http://www.unicode.org/reports/tr22/

  *

  * This is useful for example for

  * - checking that a string or document can be roundtrip-converted with a converter,

  *   without/before actually performing the conversion

  * - testing if a converter can be used for text for typical text for a certain locale,

  *   by comparing its roundtrip set with the set of ExemplarCharacters from

  *   ICU's locale data or other sources

  *

  * 2. UCNV_ROUNDTRIP_AND_FALLBACK_SET

  *

  * The set of all Unicode code points that can be converted with the converter (ucnv_fromUnicode())

  * when fallbacks are turned on (see ucnv_setFallback()).

  * This set includes all code points with roundtrips and fallbacks (but not reverse fallbacks).

  *

  * In the future, there may be more UConverterUnicodeSet choices to select

  * sets with different properties.

  *

  * @param cnv The converter for which a set is requested.

  * @param setFillIn A valid USet *. It will be cleared by this function before

  *            the converter's specific set is filled into the USet.

  * @param whichSet A UConverterUnicodeSet selector;

  *              currently UCNV_ROUNDTRIP_SET is the only supported value.

  * @param pErrorCode ICU error code in/out parameter.

  *                   Must fulfill U_SUCCESS before the function call.

  *

  * @see UConverterUnicodeSet

  * @see uset_open

  * @see uset_close

  * @stable ICU 2.6

  */

 U_STABLE void U_EXPORT2

 ucnv_getUnicodeSet(const UConverter *cnv,

                    USet *setFillIn,

                    UConverterUnicodeSet whichSet,

                    UErrorCode *pErrorCode);

 /**

  * Gets the current calback function used by the converter when an illegal

  *  or invalid codepage sequence is found. 

  * Context pointers are always owned by the caller.

  *

  * @param converter the unicode converter

  * @param action fillin: returns the callback function pointer

  * @param context fillin: returns the callback's private void* context

  * @see ucnv_setToUCallBack

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getToUCallBack (const UConverter * converter,

                      UConverterToUCallback *action,

                      const void **context);

 /**

  * Gets the current callback function used by the converter when illegal 

  * or invalid Unicode sequence is found.

  * Context pointers are always owned by the caller.

  *

  * @param converter the unicode converter

  * @param action fillin: returns the callback function pointer

  * @param context fillin: returns the callback's private void* context

  * @see ucnv_setFromUCallBack

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_getFromUCallBack (const UConverter * converter,

                        UConverterFromUCallback *action,

                        const void **context);

 /**

  * Changes the callback function used by the converter when

  * an illegal or invalid sequence is found.

  * Context pointers are always owned by the caller.

  * Predefined actions and contexts can be found in the ucnv_err.h header.

  *

  * @param converter the unicode converter

  * @param newAction the new callback function

  * @param newContext the new toUnicode callback context pointer. This can be NULL.

  * @param oldAction fillin: returns the old callback function pointer. This can be NULL.

  * @param oldContext fillin: returns the old callback's private void* context. This can be NULL.

  * @param err The error code status

  * @see ucnv_getToUCallBack

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_setToUCallBack (UConverter * converter,

                      UConverterToUCallback newAction,

                      const void* newContext,

                      UConverterToUCallback *oldAction,

                      const void** oldContext,

                      UErrorCode * err);

 /**

  * Changes the current callback function used by the converter when

  * an illegal or invalid sequence is found.

  * Context pointers are always owned by the caller.

  * Predefined actions and contexts can be found in the ucnv_err.h header.

  *

  * @param converter the unicode converter

  * @param newAction the new callback function

  * @param newContext the new fromUnicode callback context pointer. This can be NULL.

  * @param oldAction fillin: returns the old callback function pointer. This can be NULL.

  * @param oldContext fillin: returns the old callback's private void* context. This can be NULL.

  * @param err The error code status

  * @see ucnv_getFromUCallBack

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_setFromUCallBack (UConverter * converter,

                        UConverterFromUCallback newAction,

                        const void *newContext,

                        UConverterFromUCallback *oldAction,

                        const void **oldContext,

                        UErrorCode * err);

 /**

  * Converts an array of unicode characters to an array of codepage

  * characters. This function is optimized for converting a continuous

  * stream of data in buffer-sized chunks, where the entire source and

  * target does not fit in available buffers.

  * 

  * The source pointer is an in/out parameter. It starts out pointing where the 

  * conversion is to begin, and ends up pointing after the last UChar consumed. 

  * 

  * Target similarly starts out pointer at the first available byte in the output

  * buffer, and ends up pointing after the last byte written to the output.

  * 

  * The converter always attempts to consume the entire source buffer, unless 

  * (1.) the target buffer is full, or (2.) a failing error is returned from the

  * current callback function.  When a successful error status has been

  * returned, it means that all of the source buffer has been

  *  consumed. At that point, the caller should reset the source and

  *  sourceLimit pointers to point to the next chunk.

  * 

  * At the end of the stream (flush==TRUE), the input is completely consumed

  * when *source==sourceLimit and no error code is set.

  * The converter object is then automatically reset by this function.

  * (This means that a converter need not be reset explicitly between data

  * streams if it finishes the previous stream without errors.)

  * 

  * This is a <I>stateful</I> conversion. Additionally, even when all source data has

  * been consumed, some data may be in the converters' internal state.

  * Call this function repeatedly, updating the target pointers with

  * the next empty chunk of target in case of a

  * <TT>U_BUFFER_OVERFLOW_ERROR</TT>, and updating the source  pointers

  *  with the next chunk of source when a successful error status is

  * returned, until there are no more chunks of source data.

  * @param converter the Unicode converter

  * @param target I/O parameter. Input : Points to the beginning of the buffer to copy

  *  codepage characters to. Output : points to after the last codepage character copied

  *  to <TT>target</TT>.

  * @param targetLimit the pointer just after last of the <TT>target</TT> buffer

  * @param source I/O parameter, pointer to pointer to the source Unicode character buffer. 

  * @param sourceLimit the pointer just after the last of the source buffer

  * @param offsets if NULL is passed, nothing will happen to it, otherwise it needs to have the same number

  * of allocated cells as <TT>target</TT>. Will fill in offsets from target to source pointer

  * 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>

  * For output data carried across calls, and other data without a specific source character

  * (such as from escape sequences or callbacks)  -1 will be placed for offsets. 

  * @param flush set to <TT>TRUE</TT> if the current source buffer is the last available

  * chunk of the source, <TT>FALSE</TT> otherwise. Note that if a failing status is returned,

  * this function may have to be called multiple times with flush set to <TT>TRUE</TT> until

  * the source buffer is consumed.

  * @param err the error status.  <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> will be set if the

  * converter is <TT>NULL</TT>.

  * <code>U_BUFFER_OVERFLOW_ERROR</code> will be set if the target is full and there is 

  * still data to be written to the target.

  * @see ucnv_fromUChars

  * @see ucnv_convert

  * @see ucnv_getMinCharSize

  * @see ucnv_setToUCallBack

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2 

 ucnv_fromUnicode (UConverter * converter,

                   char **target,

                   const char *targetLimit,

                   const UChar ** source,

                   const UChar * sourceLimit,

                   int32_t* offsets,

                   UBool flush,

                   UErrorCode * err);

 /**

  * Converts a buffer of codepage bytes into an array of unicode UChars

  * characters. This function is optimized for converting a continuous

  * stream of data in buffer-sized chunks, where the entire source and

  * target does not fit in available buffers.

  * 

  * The source pointer is an in/out parameter. It starts out pointing where the 

  * conversion is to begin, and ends up pointing after the last byte of source consumed. 

  * 

  * Target similarly starts out pointer at the first available UChar in the output

  * buffer, and ends up pointing after the last UChar written to the output. 

  * It does NOT necessarily keep UChar sequences together.

  * 

  * The converter always attempts to consume the entire source buffer, unless 

  * (1.) the target buffer is full, or (2.) a failing error is returned from the

  * current callback function.  When a successful error status has been

  * returned, it means that all of the source buffer has been

  *  consumed. At that point, the caller should reset the source and

  *  sourceLimit pointers to point to the next chunk.

  *

  * At the end of the stream (flush==TRUE), the input is completely consumed

  * when *source==sourceLimit and no error code is set

  * The converter object is then automatically reset by this function.

  * (This means that a converter need not be reset explicitly between data

  * streams if it finishes the previous stream without errors.)

  * 

  * This is a <I>stateful</I> conversion. Additionally, even when all source data has

  * been consumed, some data may be in the converters' internal state.

  * Call this function repeatedly, updating the target pointers with

  * the next empty chunk of target in case of a

  * <TT>U_BUFFER_OVERFLOW_ERROR</TT>, and updating the source  pointers

  *  with the next chunk of source when a successful error status is

  * returned, until there are no more chunks of source data.

  * @param converter the Unicode converter

  * @param target I/O parameter. Input : Points to the beginning of the buffer to copy

  *  UChars into. Output : points to after the last UChar copied.

  * @param targetLimit the pointer just after the end of the <TT>target</TT> buffer

  * @param source I/O parameter, pointer to pointer to the source codepage buffer. 

  * @param sourceLimit the pointer to the byte after the end of the source buffer

  * @param offsets if NULL is passed, nothing will happen to it, otherwise it needs to have the same number

  * of allocated cells as <TT>target</TT>. Will fill in offsets from target to source pointer

  * 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>

  * For output data carried across calls, and other data without a specific source character

  * (such as from escape sequences or callbacks)  -1 will be placed for offsets. 

  * @param flush set to <TT>TRUE</TT> if the current source buffer is the last available

  * chunk of the source, <TT>FALSE</TT> otherwise. Note that if a failing status is returned,

  * this function may have to be called multiple times with flush set to <TT>TRUE</TT> until

  * the source buffer is consumed.

  * @param err the error status.  <TT>U_ILLEGAL_ARGUMENT_ERROR</TT> will be set if the

  * converter is <TT>NULL</TT>.

  * <code>U_BUFFER_OVERFLOW_ERROR</code> will be set if the target is full and there is 

  * still data to be written to the target. 

  * @see ucnv_fromUChars

  * @see ucnv_convert

  * @see ucnv_getMinCharSize

  * @see ucnv_setFromUCallBack

  * @see ucnv_getNextUChar

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2 

 ucnv_toUnicode(UConverter *converter,

                UChar **target,

                const UChar *targetLimit,

                const char **source,

                const char *sourceLimit,

                int32_t *offsets,

                UBool flush,

                UErrorCode *err);

 /**

  * Convert the Unicode string into a codepage string using an existing UConverter.

  * The output string is NUL-terminated if possible.

  *

  * This function is a more convenient but less powerful version of ucnv_fromUnicode().

  * It is only useful for whole strings, not for streaming conversion.

  *

  * The maximum output buffer capacity required (barring output from callbacks) will be

  * UCNV_GET_MAX_BYTES_FOR_STRING(srcLength, ucnv_getMaxCharSize(cnv)).

  *

  * @param cnv the converter object to be used (ucnv_resetFromUnicode() will be called)

  * @param src the input Unicode string

  * @param srcLength the input string length, or -1 if NUL-terminated

  * @param dest destination string buffer, can be NULL if destCapacity==0

  * @param destCapacity the number of chars available at dest

  * @param pErrorCode normal ICU error code;

  *                  common error codes that may be set by this function include

  *                  U_BUFFER_OVERFLOW_ERROR, U_STRING_NOT_TERMINATED_WARNING,

  *                  U_ILLEGAL_ARGUMENT_ERROR, and conversion errors

  * @return the length of the output string, not counting the terminating NUL;

  *         if the length is greater than destCapacity, then the string will not fit

  *         and a buffer of the indicated length would need to be passed in

  * @see ucnv_fromUnicode

  * @see ucnv_convert

  * @see UCNV_GET_MAX_BYTES_FOR_STRING

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_fromUChars(UConverter *cnv,

                 char *dest, int32_t destCapacity,

                 const UChar *src, int32_t srcLength,

                 UErrorCode *pErrorCode);

 /**

  * Convert the codepage string into a Unicode string using an existing UConverter.

  * The output string is NUL-terminated if possible.

  *

  * This function is a more convenient but less powerful version of ucnv_toUnicode().

  * It is only useful for whole strings, not for streaming conversion.

  *

  * The maximum output buffer capacity required (barring output from callbacks) will be

  * 2*srcLength (each char may be converted into a surrogate pair).

  *

  * @param cnv the converter object to be used (ucnv_resetToUnicode() will be called)

  * @param src the input codepage string

  * @param srcLength the input string length, or -1 if NUL-terminated

  * @param dest destination string buffer, can be NULL if destCapacity==0

  * @param destCapacity the number of UChars available at dest

  * @param pErrorCode normal ICU error code;

  *                  common error codes that may be set by this function include

  *                  U_BUFFER_OVERFLOW_ERROR, U_STRING_NOT_TERMINATED_WARNING,

  *                  U_ILLEGAL_ARGUMENT_ERROR, and conversion errors

  * @return the length of the output string, not counting the terminating NUL;

  *         if the length is greater than destCapacity, then the string will not fit

  *         and a buffer of the indicated length would need to be passed in

  * @see ucnv_toUnicode

  * @see ucnv_convert

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_toUChars(UConverter *cnv,

               UChar *dest, int32_t destCapacity,

               const char *src, int32_t srcLength,

               UErrorCode *pErrorCode);

 /**

  * Convert a codepage buffer into Unicode one character at a time.

  * The input is completely consumed when the U_INDEX_OUTOFBOUNDS_ERROR is set.

  *

  * Advantage compared to ucnv_toUnicode() or ucnv_toUChars():

  * - Faster for small amounts of data, for most converters, e.g.,

  *   US-ASCII, ISO-8859-1, UTF-8/16/32, and most "normal" charsets.

  *   (For complex converters, e.g., SCSU, UTF-7 and ISO 2022 variants,

  *    it uses ucnv_toUnicode() internally.)

  * - Convenient.

  *

  * Limitations compared to ucnv_toUnicode():

  * - Always assumes flush=TRUE.

  *   This makes ucnv_getNextUChar() unsuitable for "streaming" conversion,

  *   that is, for where the input is supplied in multiple buffers,

  *   because ucnv_getNextUChar() will assume the end of the input at the end

  *   of the first buffer.

  * - Does not provide offset output.

  *

  * It is possible to "mix" ucnv_getNextUChar() and ucnv_toUnicode() because

  * ucnv_getNextUChar() uses the current state of the converter

  * (unlike ucnv_toUChars() which always resets first).

  * However, if ucnv_getNextUChar() is called after ucnv_toUnicode()

  * stopped in the middle of a character sequence (with flush=FALSE),

  * then ucnv_getNextUChar() will always use the slower ucnv_toUnicode()

  * internally until the next character boundary.

  * (This is new in ICU 2.6. In earlier releases, ucnv_getNextUChar() had to

  * start at a character boundary.)

  *

  * Instead of using ucnv_getNextUChar(), it is recommended

  * to convert using ucnv_toUnicode() or ucnv_toUChars()

  * and then iterate over the text using U16_NEXT() or a UCharIterator (uiter.h)

  * or a C++ CharacterIterator or similar.

  * This allows streaming conversion and offset output, for example.

  *

  * <p>Handling of surrogate pairs and supplementary-plane code points:<br>

  * There are two different kinds of codepages that provide mappings for surrogate characters:

  * <ul>

  *   <li>Codepages like UTF-8, UTF-32, and GB 18030 provide direct representations for Unicode

  *       code points U+10000-U+10ffff as well as for single surrogates U+d800-U+dfff.

  *       Each valid sequence will result in exactly one returned code point.

  *       If a sequence results in a single surrogate, then that will be returned

  *       by itself, even if a neighboring sequence encodes the matching surrogate.</li>

  *   <li>Codepages like SCSU and LMBCS (and UTF-16) provide direct representations only for BMP code points

  *       including surrogates. Code points in supplementary planes are represented with

  *       two sequences, each encoding a surrogate.

  *       For these codepages, matching pairs of surrogates will be combined into single

  *       code points for returning from this function.

  *       (Note that SCSU is actually a mix of these codepage types.)</li>

  * </ul></p>

  *

  * @param converter an open UConverter

  * @param source the address of a pointer to the codepage buffer, will be

  *  updated to point after the bytes consumed in the conversion call.

  * @param sourceLimit points to the end of the input buffer

  * @param err fills in error status (see ucnv_toUnicode)

  * <code>U_INDEX_OUTOFBOUNDS_ERROR</code> will be set if the input 

  * is empty or does not convert to any output (e.g.: pure state-change 

  * codes SI/SO, escape sequences for ISO 2022,

  * or if the callback did not output anything, ...).

  * This function will not set a <code>U_BUFFER_OVERFLOW_ERROR</code> because

  *  the "buffer" is the return code. However, there might be subsequent output

  *  stored in the converter object

  * that will be returned in following calls to this function.

  * @return a UChar32 resulting from the partial conversion of source

  * @see ucnv_toUnicode

  * @see ucnv_toUChars

  * @see ucnv_convert

  * @stable ICU 2.0

  */

 U_STABLE UChar32 U_EXPORT2

 ucnv_getNextUChar(UConverter * converter,

                   const char **source,

                   const char * sourceLimit,

                   UErrorCode * err);

 /**

  * Convert from one external charset to another using two existing UConverters.

  * Internally, two conversions - ucnv_toUnicode() and ucnv_fromUnicode() -

  * are used, "pivoting" through 16-bit Unicode.

  *

  * Important: For streaming conversion (multiple function calls for successive

  * parts of a text stream), the caller must provide a pivot buffer explicitly,

  * and must preserve the pivot buffer and associated pointers from one

  * call to another. (The buffer may be moved if its contents and the relative

  * pointer positions are preserved.)

  *

  * There is a similar function, ucnv_convert(),

  * which has the following limitations:

  * - it takes charset names, not converter objects, so that

  *   - two converters are opened for each call

  *   - only single-string conversion is possible, not streaming operation

  * - it does not provide enough information to find out,

  *   in case of failure, whether the toUnicode or

  *   the fromUnicode conversion failed

  *

  * By contrast, ucnv_convertEx()

  * - takes UConverter parameters instead of charset names

  * - fully exposes the pivot buffer for streaming conversion and complete error handling

  *

  * ucnv_convertEx() also provides further convenience:

  * - an option to reset the converters at the beginning

  *   (if reset==TRUE, see parameters;

  *    also sets *pivotTarget=*pivotSource=pivotStart)

  * - allow NUL-terminated input

  *   (only a single NUL byte, will not work for charsets with multi-byte NULs)

  *   (if sourceLimit==NULL, see parameters)

  * - terminate with a NUL on output

  *   (only a single NUL byte, not useful for charsets with multi-byte NULs),

  *   or set U_STRING_NOT_TERMINATED_WARNING if the output exactly fills

  *   the target buffer

  * - the pivot buffer can be provided internally;

  *   possible only for whole-string conversion, not streaming conversion;

  *   in this case, the caller will not be able to get details about where an

  *   error occurred

  *   (if pivotStart==NULL, see below)

  *

  * The function returns when one of the following is true:

  * - the entire source text has been converted successfully to the target buffer

  * - a target buffer overflow occurred (U_BUFFER_OVERFLOW_ERROR)

  * - a conversion error occurred

  *   (other U_FAILURE(), see description of pErrorCode)

  *

  * Limitation compared to the direct use of

  * ucnv_fromUnicode() and ucnv_toUnicode():

  * ucnv_convertEx() does not provide offset information.

  *

  * Limitation compared to ucnv_fromUChars() and ucnv_toUChars():

  * ucnv_convertEx() does not support preflighting directly.

  *

  * Sample code for converting a single string from

  * one external charset to UTF-8, ignoring the location of errors:

  *

  * \code

  * int32_t

  * myToUTF8(UConverter *cnv,

  *          const char *s, int32_t length,

  *          char *u8, int32_t capacity,

  *          UErrorCode *pErrorCode) {

  *     UConverter *utf8Cnv;

  *     char *target;

  *

  *     if(U_FAILURE(*pErrorCode)) {

  *         return 0;

  *     }

  *

  *     utf8Cnv=myGetCachedUTF8Converter(pErrorCode);

  *     if(U_FAILURE(*pErrorCode)) {

  *         return 0;

  *     }

  *

  *     if(length<0) {

  *         length=strlen(s);

  *     }

  *     target=u8;

  *     ucnv_convertEx(utf8Cnv, cnv,

  *                    &target, u8+capacity,

  *                    &s, s+length,

  *                    NULL, NULL, NULL, NULL,

  *                    TRUE, TRUE,

  *                    pErrorCode);

  * 

  *     myReleaseCachedUTF8Converter(utf8Cnv);

  *

  *     // return the output string length, but without preflighting

  *     return (int32_t)(target-u8);

  * }

  * \endcode

  *

  * @param targetCnv     Output converter, used to convert from the UTF-16 pivot

  *                      to the target using ucnv_fromUnicode().

  * @param sourceCnv     Input converter, used to convert from the source to

  *                      the UTF-16 pivot using ucnv_toUnicode().

  * @param target        I/O parameter, same as for ucnv_fromUChars().

  *                      Input: *target points to the beginning of the target buffer.

  *                      Output: *target points to the first unit after the last char written.

  * @param targetLimit   Pointer to the first unit after the target buffer.

  * @param source        I/O parameter, same as for ucnv_toUChars().

  *                      Input: *source points to the beginning of the source buffer.

  *                      Output: *source points to the first unit after the last char read.

  * @param sourceLimit   Pointer to the first unit after the source buffer.

  * @param pivotStart    Pointer to the UTF-16 pivot buffer. If pivotStart==NULL,

  *                      then an internal buffer is used and the other pivot

  *                      arguments are ignored and can be NULL as well.

  * @param pivotSource   I/O parameter, same as source in ucnv_fromUChars() for

  *                      conversion from the pivot buffer to the target buffer.

  * @param pivotTarget   I/O parameter, same as target in ucnv_toUChars() for

  *                      conversion from the source buffer to the pivot buffer.

  *                      It must be pivotStart<=*pivotSource<=*pivotTarget<=pivotLimit

  *                      and pivotStart<pivotLimit (unless pivotStart==NULL).

  * @param pivotLimit    Pointer to the first unit after the pivot buffer.

  * @param reset         If TRUE, then ucnv_resetToUnicode(sourceCnv) and

  *                      ucnv_resetFromUnicode(targetCnv) are called, and the

  *                      pivot pointers are reset (*pivotTarget=*pivotSource=pivotStart).

  * @param flush         If true, indicates the end of the input.

  *                      Passed directly to ucnv_toUnicode(), and carried over to

  *                      ucnv_fromUnicode() when the source is empty as well.

  * @param pErrorCode    ICU error code in/out parameter.

  *                      Must fulfill U_SUCCESS before the function call.

  *                      U_BUFFER_OVERFLOW_ERROR always refers to the target buffer

  *                      because overflows into the pivot buffer are handled internally.

  *                      Other conversion errors are from the source-to-pivot

  *                      conversion if *pivotSource==pivotStart, otherwise from

  *                      the pivot-to-target conversion.

  *

  * @see ucnv_convert

  * @see ucnv_fromAlgorithmic

  * @see ucnv_toAlgorithmic

  * @see ucnv_fromUnicode

  * @see ucnv_toUnicode

  * @see ucnv_fromUChars

  * @see ucnv_toUChars

  * @stable ICU 2.6

  */

 U_STABLE void U_EXPORT2

 ucnv_convertEx(UConverter *targetCnv, UConverter *sourceCnv,

                char **target, const char *targetLimit,

                const char **source, const char *sourceLimit,

                UChar *pivotStart, UChar **pivotSource,

                UChar **pivotTarget, const UChar *pivotLimit,

                UBool reset, UBool flush,

                UErrorCode *pErrorCode);

 /**

  * Convert from one external charset to another.

  * Internally, two converters are opened according to the name arguments,

  * then the text is converted to and from the 16-bit Unicode "pivot"

  * using ucnv_convertEx(), then the converters are closed again.

  *

  * This is a convenience function, not an efficient way to convert a lot of text:

  * ucnv_convert()

  * - takes charset names, not converter objects, so that

  *   - two converters are opened for each call

  *   - only single-string conversion is possible, not streaming operation

  * - does not provide enough information to find out,

  *   in case of failure, whether the toUnicode or

  *   the fromUnicode conversion failed

  * - allows NUL-terminated input

  *   (only a single NUL byte, will not work for charsets with multi-byte NULs)

  *   (if sourceLength==-1, see parameters)

  * - terminate with a NUL on output

  *   (only a single NUL byte, not useful for charsets with multi-byte NULs),

  *   or set U_STRING_NOT_TERMINATED_WARNING if the output exactly fills

  *   the target buffer

  * - a pivot buffer is provided internally

  *

  * The function returns when one of the following is true:

  * - the entire source text has been converted successfully to the target buffer

  *   and either the target buffer is terminated with a single NUL byte

  *   or the error code is set to U_STRING_NOT_TERMINATED_WARNING

  * - a target buffer overflow occurred (U_BUFFER_OVERFLOW_ERROR)

  *   and the full output string length is returned ("preflighting")

  * - a conversion error occurred

  *   (other U_FAILURE(), see description of pErrorCode)

  *

  * @param toConverterName   The name of the converter that is used to convert

  *                          from the UTF-16 pivot buffer to the target.

  * @param fromConverterName The name of the converter that is used to convert

  *                          from the source to the UTF-16 pivot buffer.

  * @param target            Pointer to the output buffer.

  * @param targetCapacity    Capacity of the target, in bytes.

  * @param source            Pointer to the input buffer.

  * @param sourceLength      Length of the input text, in bytes, or -1 for NUL-terminated input.

  * @param pErrorCode        ICU error code in/out parameter.

  *                          Must fulfill U_SUCCESS before the function call.

  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity

  *         and a U_BUFFER_OVERFLOW_ERROR is set.

  *

  * @see ucnv_convertEx

  * @see ucnv_fromAlgorithmic

  * @see ucnv_toAlgorithmic

  * @see ucnv_fromUnicode

  * @see ucnv_toUnicode

  * @see ucnv_fromUChars

  * @see ucnv_toUChars

  * @see ucnv_getNextUChar

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_convert(const char *toConverterName,

              const char *fromConverterName,

              char *target,

              int32_t targetCapacity,

              const char *source,

              int32_t sourceLength,

              UErrorCode *pErrorCode);

 /**

  * Convert from one external charset to another.

  * Internally, the text is converted to and from the 16-bit Unicode "pivot"

  * using ucnv_convertEx(). ucnv_toAlgorithmic() works exactly like ucnv_convert()

  * except that the two converters need not be looked up and opened completely.

  *

  * The source-to-pivot conversion uses the cnv converter parameter.

  * The pivot-to-target conversion uses a purely algorithmic converter

  * according to the specified type, e.g., UCNV_UTF8 for a UTF-8 converter.

  *

  * Internally, the algorithmic converter is opened and closed for each

  * function call, which is more efficient than using the public ucnv_open()

  * but somewhat less efficient than only resetting an existing converter

  * and using ucnv_convertEx().

  *

  * This function is more convenient than ucnv_convertEx() for single-string

  * conversions, especially when "preflighting" is desired (returning the length

  * of the complete output even if it does not fit into the target buffer;

  * see the User Guide Strings chapter). See ucnv_convert() for details.

  *

  * @param algorithmicType   UConverterType constant identifying the desired target

  *                          charset as a purely algorithmic converter.

  *                          Those are converters for Unicode charsets like

  *                          UTF-8, BOCU-1, SCSU, UTF-7, IMAP-mailbox-name, etc.,

  *                          as well as US-ASCII and ISO-8859-1.

  * @param cnv               The converter that is used to convert

  *                          from the source to the UTF-16 pivot buffer.

  * @param target            Pointer to the output buffer.

  * @param targetCapacity    Capacity of the target, in bytes.

  * @param source            Pointer to the input buffer.

  * @param sourceLength      Length of the input text, in bytes

  * @param pErrorCode        ICU error code in/out parameter.

  *                          Must fulfill U_SUCCESS before the function call.

  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity

  *         and a U_BUFFER_OVERFLOW_ERROR is set.

  *

  * @see ucnv_fromAlgorithmic

  * @see ucnv_convert

  * @see ucnv_convertEx

  * @see ucnv_fromUnicode

  * @see ucnv_toUnicode

  * @see ucnv_fromUChars

  * @see ucnv_toUChars

  * @stable ICU 2.6

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_toAlgorithmic(UConverterType algorithmicType,

                    UConverter *cnv,

                    char *target, int32_t targetCapacity,

                    const char *source, int32_t sourceLength,

                    UErrorCode *pErrorCode);

 /**

  * Convert from one external charset to another.

  * Internally, the text is converted to and from the 16-bit Unicode "pivot"

  * using ucnv_convertEx(). ucnv_fromAlgorithmic() works exactly like ucnv_convert()

  * except that the two converters need not be looked up and opened completely.

  *

  * The source-to-pivot conversion uses a purely algorithmic converter

  * according to the specified type, e.g., UCNV_UTF8 for a UTF-8 converter.

  * The pivot-to-target conversion uses the cnv converter parameter.

  *

  * Internally, the algorithmic converter is opened and closed for each

  * function call, which is more efficient than using the public ucnv_open()

  * but somewhat less efficient than only resetting an existing converter

  * and using ucnv_convertEx().

  *

  * This function is more convenient than ucnv_convertEx() for single-string

  * conversions, especially when "preflighting" is desired (returning the length

  * of the complete output even if it does not fit into the target buffer;

  * see the User Guide Strings chapter). See ucnv_convert() for details.

  *

  * @param cnv               The converter that is used to convert

  *                          from the UTF-16 pivot buffer to the target.

  * @param algorithmicType   UConverterType constant identifying the desired source

  *                          charset as a purely algorithmic converter.

  *                          Those are converters for Unicode charsets like

  *                          UTF-8, BOCU-1, SCSU, UTF-7, IMAP-mailbox-name, etc.,

  *                          as well as US-ASCII and ISO-8859-1.

  * @param target            Pointer to the output buffer.

  * @param targetCapacity    Capacity of the target, in bytes.

  * @param source            Pointer to the input buffer.

  * @param sourceLength      Length of the input text, in bytes

  * @param pErrorCode        ICU error code in/out parameter.

  *                          Must fulfill U_SUCCESS before the function call.

  * @return Length of the complete output text in bytes, even if it exceeds the targetCapacity

  *         and a U_BUFFER_OVERFLOW_ERROR is set.

  *

  * @see ucnv_fromAlgorithmic

  * @see ucnv_convert

  * @see ucnv_convertEx

  * @see ucnv_fromUnicode

  * @see ucnv_toUnicode

  * @see ucnv_fromUChars

  * @see ucnv_toUChars

  * @stable ICU 2.6

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_fromAlgorithmic(UConverter *cnv,

                      UConverterType algorithmicType,

                      char *target, int32_t targetCapacity,

                      const char *source, int32_t sourceLength,

                      UErrorCode *pErrorCode);

 /**

  * Frees up memory occupied by unused, cached converter shared data.

  *

  * @return the number of cached converters successfully deleted

  * @see ucnv_close

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_flushCache(void);

 /**

  * Returns the number of available converters, as per the alias file.

  *

  * @return the number of available converters

  * @see ucnv_getAvailableName

  * @stable ICU 2.0

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_countAvailable(void);

 /**

  * Gets the canonical converter name of the specified converter from a list of

  * all available converters contaied in the alias file. All converters

  * in this list can be opened.

  *

  * @param n the index to a converter available on the system (in the range <TT>[0..ucnv_countAvaiable()]</TT>)

  * @return a pointer a string (library owned), or <TT>NULL</TT> if the index is out of bounds.

  * @see ucnv_countAvailable

  * @stable ICU 2.0

  */

 U_STABLE const char* U_EXPORT2

 ucnv_getAvailableName(int32_t n);

 /**

  * Returns a UEnumeration to enumerate all of the canonical converter

  * names, as per the alias file, regardless of the ability to open each

  * converter.

  *

  * @return A UEnumeration object for getting all the recognized canonical

  *   converter names.

  * @see ucnv_getAvailableName

  * @see uenum_close

  * @see uenum_next

  * @stable ICU 2.4

  */

 U_STABLE UEnumeration * U_EXPORT2

 ucnv_openAllNames(UErrorCode *pErrorCode);

 /**

  * Gives the number of aliases for a given converter or alias name.

  * If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.

  * This method only enumerates the listed entries in the alias file.

  * @param alias alias name

  * @param pErrorCode error status

  * @return number of names on alias list for given alias

  * @stable ICU 2.0

  */

 U_STABLE uint16_t U_EXPORT2 

 ucnv_countAliases(const char *alias, UErrorCode *pErrorCode);

 /**

  * Gives the name of the alias at given index of alias list.

  * This method only enumerates the listed entries in the alias file.

  * If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.

  * @param alias alias name

  * @param n index in alias list

  * @param pErrorCode result of operation

  * @return returns the name of the alias at given index

  * @see ucnv_countAliases

  * @stable ICU 2.0

  */

 U_STABLE const char * U_EXPORT2 

 ucnv_getAlias(const char *alias, uint16_t n, UErrorCode *pErrorCode);

 /**

  * Fill-up the list of alias names for the given alias.

  * This method only enumerates the listed entries in the alias file.

  * If the alias is ambiguous, then the preferred converter is used

  * and the status is set to U_AMBIGUOUS_ALIAS_WARNING.

  * @param alias alias name

  * @param aliases fill-in list, aliases is a pointer to an array of

  *        <code>ucnv_countAliases()</code> string-pointers

  *        (<code>const char *</code>) that will be filled in.

  *        The strings themselves are owned by the library.

  * @param pErrorCode result of operation

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2 

 ucnv_getAliases(const char *alias, const char **aliases, UErrorCode *pErrorCode);

 /**

  * Return a new UEnumeration object for enumerating all the

  * alias names for a given converter that are recognized by a standard.

  * This method only enumerates the listed entries in the alias file.

  * The convrtrs.txt file can be modified to change the results of

  * this function.

  * The first result in this list is the same result given by

  * <code>ucnv_getStandardName</code>, which is the default alias for

  * the specified standard name. The returned object must be closed with

  * <code>uenum_close</code> when you are done with the object.

  *

  * @param convName original converter name

  * @param standard name of the standard governing the names; MIME and IANA

  *      are such standards

  * @param pErrorCode The error code

  * @return A UEnumeration object for getting all aliases that are recognized

  *      by a standard. If any of the parameters are invalid, NULL

  *      is returned.

  * @see ucnv_getStandardName

  * @see uenum_close

  * @see uenum_next

  * @stable ICU 2.2

  */

 U_STABLE UEnumeration * U_EXPORT2

 ucnv_openStandardNames(const char *convName,

                        const char *standard,

                        UErrorCode *pErrorCode);

 /**

  * Gives the number of standards associated to converter names.

  * @return number of standards

  * @stable ICU 2.0

  */

 U_STABLE uint16_t U_EXPORT2

 ucnv_countStandards(void);

 /**

  * Gives the name of the standard at given index of standard list.

  * @param n index in standard list

  * @param pErrorCode result of operation

  * @return returns the name of the standard at given index. Owned by the library.

  * @stable ICU 2.0

  */

 U_STABLE const char * U_EXPORT2

 ucnv_getStandard(uint16_t n, UErrorCode *pErrorCode);

 /**

  * Returns a standard name for a given converter name.

  * <p>

  * Example alias table:<br>

  * conv alias1 { STANDARD1 } alias2 { STANDARD1* }

  * <p>

  * Result of ucnv_getStandardName("conv", "STANDARD1") from example

  * alias table:<br>

  * <b>"alias2"</b>

  *

  * @param name original converter name

  * @param standard name of the standard governing the names; MIME and IANA

  *        are such standards

  * @param pErrorCode result of operation

  * @return returns the standard converter name;

  *         if a standard converter name cannot be determined,

  *         then <code>NULL</code> is returned. Owned by the library.

  * @stable ICU 2.0

  */

 U_STABLE const char * U_EXPORT2

 ucnv_getStandardName(const char *name, const char *standard, UErrorCode *pErrorCode);

 /**

  * This function will return the internal canonical converter name of the

  * tagged alias. This is the opposite of ucnv_openStandardNames, which

  * returns the tagged alias given the canonical name.

  * <p>

  * Example alias table:<br>

  * conv alias1 { STANDARD1 } alias2 { STANDARD1* }

  * <p>

  * Result of ucnv_getStandardName("alias1", "STANDARD1") from example

  * alias table:<br>

  * <b>"conv"</b>

  *

  * @return returns the canonical converter name;

  *         if a standard or alias name cannot be determined,

  *         then <code>NULL</code> is returned. The returned string is

  *         owned by the library.

  * @see ucnv_getStandardName

  * @stable ICU 2.4

  */

 U_STABLE const char * U_EXPORT2

 ucnv_getCanonicalName(const char *alias, const char *standard, UErrorCode *pErrorCode);

 /**

  * Returns the current default converter name. If you want to open

  * a default converter, you do not need to use this function.

  * It is faster if you pass a NULL argument to ucnv_open the

  * default converter.

  *

  * If U_CHARSET_IS_UTF8 is defined to 1 in utypes.h then this function

  * always returns "UTF-8".

  *

  * @return returns the current default converter name.

  *         Storage owned by the library

  * @see ucnv_setDefaultName

  * @stable ICU 2.0

  */

 U_STABLE const char * U_EXPORT2

 ucnv_getDefaultName(void);

 #ifndef U_HIDE_SYSTEM_API

 /**

  * This function is not thread safe. DO NOT call this function when ANY ICU

  * function is being used from more than one thread! This function sets the

  * current default converter name. If this function needs to be called, it

  * should be called during application initialization. Most of the time, the

  * results from ucnv_getDefaultName() or ucnv_open with a NULL string argument

  * is sufficient for your application.

  *

  * If U_CHARSET_IS_UTF8 is defined to 1 in utypes.h then this function

  * does nothing.

  *

  * @param name the converter name to be the default (must be known by ICU).

  * @see ucnv_getDefaultName

  * @system

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_setDefaultName(const char *name);

 #endif  /* U_HIDE_SYSTEM_API */

 /**

  * Fixes the backslash character mismapping.  For example, in SJIS, the backslash 

  * character in the ASCII portion is also used to represent the yen currency sign.  

  * When mapping from Unicode character 0x005C, it's unclear whether to map the 

  * character back to yen or backslash in SJIS.  This function will take the input

  * buffer and replace all the yen sign characters with backslash.  This is necessary

  * when the user tries to open a file with the input buffer on Windows.

  * This function will test the converter to see whether such mapping is

  * required.  You can sometimes avoid using this function by using the correct version

  * of Shift-JIS.

  *

  * @param cnv The converter representing the target codepage.

  * @param source the input buffer to be fixed

  * @param sourceLen the length of the input buffer

  * @see ucnv_isAmbiguous

  * @stable ICU 2.0

  */

 U_STABLE void U_EXPORT2

 ucnv_fixFileSeparator(const UConverter *cnv, UChar *source, int32_t sourceLen);

 /**

  * Determines if the converter contains ambiguous mappings of the same

  * character or not.

  * @param cnv the converter to be tested

  * @return TRUE if the converter contains ambiguous mapping of the same 

  * character, FALSE otherwise.

  * @stable ICU 2.0

  */

 U_STABLE UBool U_EXPORT2

 ucnv_isAmbiguous(const UConverter *cnv);

 /**

  * Sets the converter to use fallback mappings or not.

  * Regardless of this flag, the converter will always use

  * fallbacks from Unicode Private Use code points, as well as

  * reverse fallbacks (to Unicode).

  * For details see ".ucm File Format"

  * in the Conversion Data chapter of the ICU User Guide:

  * http://www.icu-project.org/userguide/conversion-data.html#ucmformat

  *

  * @param cnv The converter to set the fallback mapping usage on.

  * @param usesFallback TRUE if the user wants the converter to take advantage of the fallback 

  * mapping, FALSE otherwise.

  * @stable ICU 2.0

  * @see ucnv_usesFallback

  */

 U_STABLE void U_EXPORT2 

 ucnv_setFallback(UConverter *cnv, UBool usesFallback);

 /**

  * Determines if the converter uses fallback mappings or not.

  * This flag has restrictions, see ucnv_setFallback().

  *

  * @param cnv The converter to be tested

  * @return TRUE if the converter uses fallback, FALSE otherwise.

  * @stable ICU 2.0

  * @see ucnv_setFallback

  */

 U_STABLE UBool U_EXPORT2 

 ucnv_usesFallback(const UConverter *cnv);

 /**

  * Detects Unicode signature byte sequences at the start of the byte stream

  * and returns the charset name of the indicated Unicode charset.

  * NULL is returned when no Unicode signature is recognized.

  * The number of bytes in the signature is output as well.

  *

  * The caller can ucnv_open() a converter using the charset name.

  * The first code unit (UChar) from the start of the stream will be U+FEFF

  * (the Unicode BOM/signature character) and can usually be ignored.

  *

  * For most Unicode charsets it is also possible to ignore the indicated

  * number of initial stream bytes and start converting after them.

  * However, there are stateful Unicode charsets (UTF-7 and BOCU-1) for which

  * this will not work. Therefore, it is best to ignore the first output UChar

  * instead of the input signature bytes.

  * <p>

  * Usage:

  * \snippet samples/ucnv/convsamp.cpp ucnv_detectUnicodeSignature

  *

  * @param source            The source string in which the signature should be detected.

  * @param sourceLength      Length of the input string, or -1 if terminated with a NUL byte.

  * @param signatureLength   A pointer to int32_t to receive the number of bytes that make up the signature 

  *                          of the detected UTF. 0 if not detected.

  *                          Can be a NULL pointer.

  * @param pErrorCode        ICU error code in/out parameter.

  *                          Must fulfill U_SUCCESS before the function call.

  * @return The name of the encoding detected. NULL if encoding is not detected. 

  * @stable ICU 2.4

  */

 U_STABLE const char* U_EXPORT2

 ucnv_detectUnicodeSignature(const char* source,

                             int32_t sourceLength,

                             int32_t *signatureLength,

                             UErrorCode *pErrorCode);

 /**

  * Returns the number of UChars held in the converter's internal state 

  * because more input is needed for completing the conversion. This function is 

  * useful for mapping semantics of ICU's converter interface to those of iconv,

  * and this information is not needed for normal conversion.

  * @param cnv       The converter in which the input is held

  * @param status    ICU error code in/out parameter.

  *                  Must fulfill U_SUCCESS before the function call.

  * @return The number of UChars in the state. -1 if an error is encountered.

  * @stable ICU 3.4

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_fromUCountPending(const UConverter* cnv, UErrorCode* status);

 /**

  * Returns the number of chars held in the converter's internal state

  * because more input is needed for completing the conversion. This function is 

  * useful for mapping semantics of ICU's converter interface to those of iconv,

  * and this information is not needed for normal conversion.

  * @param cnv       The converter in which the input is held as internal state

  * @param status    ICU error code in/out parameter.

  *                  Must fulfill U_SUCCESS before the function call.

  * @return The number of chars in the state. -1 if an error is encountered.

  * @stable ICU 3.4

  */

 U_STABLE int32_t U_EXPORT2

 ucnv_toUCountPending(const UConverter* cnv, UErrorCode* status);

 /**

  * Returns whether or not the charset of the converter has a fixed number of bytes

  * per charset character.

  * An example of this are converters that are of the type UCNV_SBCS or UCNV_DBCS.

  * Another example is UTF-32 which is always 4 bytes per character.

  * A Unicode code point may be represented by more than one UTF-8 or UTF-16 code unit

  * but a UTF-32 converter encodes each code point with 4 bytes.

  * Note: This method is not intended to be used to determine whether the charset has a

  * fixed ratio of bytes to Unicode codes <i>units</i> for any particular Unicode encoding form.

  * FALSE is returned with the UErrorCode if error occurs or cnv is NULL.

  * @param cnv       The converter to be tested

  * @param status    ICU error code in/out paramter

  * @return TRUE if the converter is fixed-width

  * @stable ICU 4.8

  */

 U_STABLE UBool U_EXPORT2

 ucnv_isFixedWidth(UConverter *cnv, UErrorCode *status);

 #endif

 #endif

 /*_UCNV*/