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/* ******************************************************************************* * Copyright (C) 1997-2005, International Business Machines * Corporation and others. All Rights Reserved. ******************************************************************************* * Date Name Description * 06/21/00 aliu Creation. ******************************************************************************* */ #ifndef UTRANS_H #define UTRANS_H #include "unicode/utypes.h" #if !UCONFIG_NO_TRANSLITERATION #include "unicode/urep.h" #include "unicode/parseerr.h" #include "unicode/uenum.h" /******************************************************************** * General Notes ******************************************************************** */ /** * \file * \brief C API: Transliterator * * <h2> Transliteration </h2> * The data structures and functions described in this header provide * transliteration services. Transliteration services are implemented * as C++ classes. The comments and documentation in this header * assume the reader is familiar with the C++ headers translit.h and * associated documentation. * * A significant but incomplete subset of the C++ transliteration * services are available to C code through this header. In order to * access more complex transliteration services, refer to the C++ * headers and documentation. * * There are two sets of functions for working with transliterator IDs: * * An old, deprecated set uses char * IDs, which works for true and pure * identifiers that these APIs were designed for, * for example "Cyrillic-Latin". * It does not work when the ID contains filters ("[:Script=Cyrl:]") * or even a complete set of rules because then the ID string contains more * than just "invariant" characters (see utypes.h). * * A new set of functions replaces the old ones and uses UChar * IDs, * paralleling the UnicodeString IDs in the C++ API. (New in ICU 2.8.) */ /******************************************************************** * Data Structures ********************************************************************/ /** * An opaque transliterator for use in C. Open with utrans_openxxx() * and close with utrans_close() when done. Equivalent to the C++ class * Transliterator and its subclasses. * @see Transliterator * @stable ICU 2.0 */ typedef void* UTransliterator; /** * Direction constant indicating the direction in a transliterator, * e.g., the forward or reverse rules of a RuleBasedTransliterator. * Specified when a transliterator is opened. An "A-B" transliterator * transliterates A to B when operating in the forward direction, and * B to A when operating in the reverse direction. * @stable ICU 2.0 */ typedef enum UTransDirection { /** * UTRANS_FORWARD means from <source> to <target> for a * transliterator with ID <source>-<target>. For a transliterator * opened using a rule, it means forward direction rules, e.g., * "A > B". */ UTRANS_FORWARD, /** * UTRANS_REVERSE means from <target> to <source> for a * transliterator with ID <source>-<target>. For a transliterator * opened using a rule, it means reverse direction rules, e.g., * "A < B". */ UTRANS_REVERSE } UTransDirection; /** * Position structure for utrans_transIncremental() incremental * transliteration. This structure defines two substrings of the text * being transliterated. The first region, [contextStart, * contextLimit), defines what characters the transliterator will read * as context. The second region, [start, limit), defines what * characters will actually be transliterated. The second region * should be a subset of the first. * * <p>After a transliteration operation, some of the indices in this * structure will be modified. See the field descriptions for * details. * * <p>contextStart <= start <= limit <= contextLimit * * <p>Note: All index values in this structure must be at code point * boundaries. That is, none of them may occur between two code units * of a surrogate pair. If any index does split a surrogate pair, * results are unspecified. * * @stable ICU 2.0 */ typedef struct UTransPosition { /** * Beginning index, inclusive, of the context to be considered for * a transliteration operation. The transliterator will ignore * anything before this index. INPUT/OUTPUT parameter: This parameter * is updated by a transliteration operation to reflect the maximum * amount of antecontext needed by a transliterator. * @stable ICU 2.4 */ int32_t contextStart; /** * Ending index, exclusive, of the context to be considered for a * transliteration operation. The transliterator will ignore * anything at or after this index. INPUT/OUTPUT parameter: This * parameter is updated to reflect changes in the length of the * text, but points to the same logical position in the text. * @stable ICU 2.4 */ int32_t contextLimit; /** * Beginning index, inclusive, of the text to be transliteratd. * INPUT/OUTPUT parameter: This parameter is advanced past * characters that have already been transliterated by a * transliteration operation. * @stable ICU 2.4 */ int32_t start; /** * Ending index, exclusive, of the text to be transliteratd. * INPUT/OUTPUT parameter: This parameter is updated to reflect * changes in the length of the text, but points to the same * logical position in the text. * @stable ICU 2.4 */ int32_t limit; } UTransPosition; /******************************************************************** * General API ********************************************************************/ /** * Open a custom transliterator, given a custom rules string * OR * a system transliterator, given its ID. * Any non-NULL result from this function should later be closed with * utrans_close(). * * @param id a valid transliterator ID * @param idLength the length of the ID string, or -1 if NUL-terminated * @param dir the desired direction * @param rules the transliterator rules. See the C++ header rbt.h for * rules syntax. If NULL then a system transliterator matching * the ID is returned. * @param rulesLength the length of the rules, or -1 if the rules * are NUL-terminated. * @param parseError a pointer to a UParseError struct to receive the details * of any parsing errors. This parameter may be NULL if no * parsing error details are desired. * @param pErrorCode a pointer to the UErrorCode * @return a transliterator pointer that may be passed to other * utrans_xxx() functions, or NULL if the open call fails. * @stable ICU 2.8 */ U_STABLE UTransliterator* U_EXPORT2 utrans_openU(const UChar *id, int32_t idLength, UTransDirection dir, const UChar *rules, int32_t rulesLength, UParseError *parseError, UErrorCode *pErrorCode); /** * Open an inverse of an existing transliterator. For this to work, * the inverse must be registered with the system. For example, if * the Transliterator "A-B" is opened, and then its inverse is opened, * the result is the Transliterator "B-A", if such a transliterator is * registered with the system. Otherwise the result is NULL and a * failing UErrorCode is set. Any non-NULL result from this function * should later be closed with utrans_close(). * * @param trans the transliterator to open the inverse of. * @param status a pointer to the UErrorCode * @return a pointer to a newly-opened transliterator that is the * inverse of trans, or NULL if the open call fails. * @stable ICU 2.0 */ U_STABLE UTransliterator* U_EXPORT2 utrans_openInverse(const UTransliterator* trans, UErrorCode* status); /** * Create a copy of a transliterator. Any non-NULL result from this * function should later be closed with utrans_close(). * * @param trans the transliterator to be copied. * @param status a pointer to the UErrorCode * @return a transliterator pointer that may be passed to other * utrans_xxx() functions, or NULL if the clone call fails. * @stable ICU 2.0 */ U_STABLE UTransliterator* U_EXPORT2 utrans_clone(const UTransliterator* trans, UErrorCode* status); /** * Close a transliterator. Any non-NULL pointer returned by * utrans_openXxx() or utrans_clone() should eventually be closed. * @param trans the transliterator to be closed. * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_close(UTransliterator* trans); /** * Return the programmatic identifier for this transliterator. * If this identifier is passed to utrans_openU(), it will open * a transliterator equivalent to this one, if the ID has been * registered. * * @param trans the transliterator to return the ID of. * @param resultLength pointer to an output variable receiving the length * of the ID string; can be NULL * @return the NUL-terminated ID string. This pointer remains * valid until utrans_close() is called on this transliterator. * * @stable ICU 2.8 */ U_STABLE const UChar * U_EXPORT2 utrans_getUnicodeID(const UTransliterator *trans, int32_t *resultLength); /** * Register an open transliterator with the system. When * utrans_open() is called with an ID string that is equal to that * returned by utrans_getID(adoptedTrans,...), then * utrans_clone(adoptedTrans,...) is returned. * * <p>NOTE: After this call the system owns the adoptedTrans and will * close it. The user must not call utrans_close() on adoptedTrans. * * @param adoptedTrans a transliterator, typically the result of * utrans_openRules(), to be registered with the system. * @param status a pointer to the UErrorCode * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_register(UTransliterator* adoptedTrans, UErrorCode* status); /** * Unregister a transliterator from the system. After this call the * system will no longer recognize the given ID when passed to * utrans_open(). If the ID is invalid then nothing is done. * * @param id an ID to unregister * @param idLength the length of id, or -1 if id is zero-terminated * @stable ICU 2.8 */ U_STABLE void U_EXPORT2 utrans_unregisterID(const UChar* id, int32_t idLength); /** * Set the filter used by a transliterator. A filter can be used to * make the transliterator pass certain characters through untouched. * The filter is expressed using a UnicodeSet pattern. If the * filterPattern is NULL or the empty string, then the transliterator * will be reset to use no filter. * * @param trans the transliterator * @param filterPattern a pattern string, in the form accepted by * UnicodeSet, specifying which characters to apply the * transliteration to. May be NULL or the empty string to indicate no * filter. * @param filterPatternLen the length of filterPattern, or -1 if * filterPattern is zero-terminated * @param status a pointer to the UErrorCode * @see UnicodeSet * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_setFilter(UTransliterator* trans, const UChar* filterPattern, int32_t filterPatternLen, UErrorCode* status); /** * Return the number of system transliterators. * It is recommended to use utrans_openIDs() instead. * * @return the number of system transliterators. * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 utrans_countAvailableIDs(void); /** * Return a UEnumeration for the available transliterators. * * @param pErrorCode Pointer to the UErrorCode in/out parameter. * @return UEnumeration for the available transliterators. * Close with uenum_close(). * * @stable ICU 2.8 */ U_STABLE UEnumeration * U_EXPORT2 utrans_openIDs(UErrorCode *pErrorCode); /******************************************************************** * Transliteration API ********************************************************************/ /** * Transliterate a segment of a UReplaceable string. The string is * passed in as a UReplaceable pointer rep and a UReplaceableCallbacks * function pointer struct repFunc. Functions in the repFunc struct * will be called in order to modify the rep string. * * @param trans the transliterator * @param rep a pointer to the string. This will be passed to the * repFunc functions. * @param repFunc a set of function pointers that will be used to * modify the string pointed to by rep. * @param start the beginning index, inclusive; <code>0 <= start <= * limit</code>. * @param limit pointer to the ending index, exclusive; <code>start <= * limit <= repFunc->length(rep)</code>. Upon return, *limit will * contain the new limit index. The text previously occupying * <code>[start, limit)</code> has been transliterated, possibly to a * string of a different length, at <code>[start, * </code><em>new-limit</em><code>)</code>, where <em>new-limit</em> * is the return value. * @param status a pointer to the UErrorCode * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_trans(const UTransliterator* trans, UReplaceable* rep, UReplaceableCallbacks* repFunc, int32_t start, int32_t* limit, UErrorCode* status); /** * Transliterate the portion of the UReplaceable text buffer that can * be transliterated unambiguosly. This method is typically called * after new text has been inserted, e.g. as a result of a keyboard * event. The transliterator will try to transliterate characters of * <code>rep</code> between <code>index.cursor</code> and * <code>index.limit</code>. Characters before * <code>index.cursor</code> will not be changed. * * <p>Upon return, values in <code>index</code> will be updated. * <code>index.start</code> will be advanced to the first * character that future calls to this method will read. * <code>index.cursor</code> and <code>index.limit</code> will * be adjusted to delimit the range of text that future calls to * this method may change. * * <p>Typical usage of this method begins with an initial call * with <code>index.start</code> and <code>index.limit</code> * set to indicate the portion of <code>text</code> to be * transliterated, and <code>index.cursor == index.start</code>. * Thereafter, <code>index</code> can be used without * modification in future calls, provided that all changes to * <code>text</code> are made via this method. * * <p>This method assumes that future calls may be made that will * insert new text into the buffer. As a result, it only performs * unambiguous transliterations. After the last call to this method, * there may be untransliterated text that is waiting for more input * to resolve an ambiguity. In order to perform these pending * transliterations, clients should call utrans_trans() with a start * of index.start and a limit of index.end after the last call to this * method has been made. * * @param trans the transliterator * @param rep a pointer to the string. This will be passed to the * repFunc functions. * @param repFunc a set of function pointers that will be used to * modify the string pointed to by rep. * @param pos a struct containing the start and limit indices of the * text to be read and the text to be transliterated * @param status a pointer to the UErrorCode * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_transIncremental(const UTransliterator* trans, UReplaceable* rep, UReplaceableCallbacks* repFunc, UTransPosition* pos, UErrorCode* status); /** * Transliterate a segment of a UChar* string. The string is passed * in in a UChar* buffer. The string is modified in place. If the * result is longer than textCapacity, it is truncated. The actual * length of the result is returned in *textLength, if textLength is * non-NULL. *textLength may be greater than textCapacity, but only * textCapacity UChars will be written to *text, including the zero * terminator. * * @param trans the transliterator * @param text a pointer to a buffer containing the text to be * transliterated on input and the result text on output. * @param textLength a pointer to the length of the string in text. * If the length is -1 then the string is assumed to be * zero-terminated. Upon return, the new length is stored in * *textLength. If textLength is NULL then the string is assumed to * be zero-terminated. * @param textCapacity a pointer to the length of the text buffer. * Upon return, * @param start the beginning index, inclusive; <code>0 <= start <= * limit</code>. * @param limit pointer to the ending index, exclusive; <code>start <= * limit <= repFunc->length(rep)</code>. Upon return, *limit will * contain the new limit index. The text previously occupying * <code>[start, limit)</code> has been transliterated, possibly to a * string of a different length, at <code>[start, * </code><em>new-limit</em><code>)</code>, where <em>new-limit</em> * is the return value. * @param status a pointer to the UErrorCode * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_transUChars(const UTransliterator* trans, UChar* text, int32_t* textLength, int32_t textCapacity, int32_t start, int32_t* limit, UErrorCode* status); /** * Transliterate the portion of the UChar* text buffer that can be * transliterated unambiguosly. See utrans_transIncremental(). The * string is passed in in a UChar* buffer. The string is modified in * place. If the result is longer than textCapacity, it is truncated. * The actual length of the result is returned in *textLength, if * textLength is non-NULL. *textLength may be greater than * textCapacity, but only textCapacity UChars will be written to * *text, including the zero terminator. See utrans_transIncremental() * for usage details. * * @param trans the transliterator * @param text a pointer to a buffer containing the text to be * transliterated on input and the result text on output. * @param textLength a pointer to the length of the string in text. * If the length is -1 then the string is assumed to be * zero-terminated. Upon return, the new length is stored in * *textLength. If textLength is NULL then the string is assumed to * be zero-terminated. * @param textCapacity the length of the text buffer * @param pos a struct containing the start and limit indices of the * text to be read and the text to be transliterated * @param status a pointer to the UErrorCode * @see utrans_transIncremental * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 utrans_transIncrementalUChars(const UTransliterator* trans, UChar* text, int32_t* textLength, int32_t textCapacity, UTransPosition* pos, UErrorCode* status); /* deprecated API ----------------------------------------------------------- */ /* see utrans.h documentation for why these functions are deprecated */ /** * Deprecated, use utrans_openU() instead. * Open a custom transliterator, given a custom rules string * OR * a system transliterator, given its ID. * Any non-NULL result from this function should later be closed with * utrans_close(). * * @param id a valid ID, as returned by utrans_getAvailableID() * @param dir the desired direction * @param rules the transliterator rules. See the C++ header rbt.h * for rules syntax. If NULL then a system transliterator matching * the ID is returned. * @param rulesLength the length of the rules, or -1 if the rules * are zero-terminated. * @param parseError a pointer to a UParseError struct to receive the * details of any parsing errors. This parameter may be NULL if no * parsing error details are desired. * @param status a pointer to the UErrorCode * @return a transliterator pointer that may be passed to other * utrans_xxx() functions, or NULL if the open call fails. * @deprecated ICU 2.8 Use utrans_openU() instead, see utrans.h */ U_DEPRECATED UTransliterator* U_EXPORT2 utrans_open(const char* id, UTransDirection dir, const UChar* rules, /* may be Null */ int32_t rulesLength, /* -1 if null-terminated */ UParseError* parseError, /* may be Null */ UErrorCode* status); /** * Deprecated, use utrans_getUnicodeID() instead. * Return the programmatic identifier for this transliterator. * If this identifier is passed to utrans_open(), it will open * a transliterator equivalent to this one, if the ID has been * registered. * @param trans the transliterator to return the ID of. * @param buf the buffer in which to receive the ID. This may be * NULL, in which case no characters are copied. * @param bufCapacity the capacity of the buffer. Ignored if buf is * NULL. * @return the actual length of the ID, not including * zero-termination. This may be greater than bufCapacity. * @deprecated ICU 2.8 Use utrans_getUnicodeID() instead, see utrans.h */ U_DEPRECATED int32_t U_EXPORT2 utrans_getID(const UTransliterator* trans, char* buf, int32_t bufCapacity); /** * Deprecated, use utrans_unregisterID() instead. * Unregister a transliterator from the system. After this call the * system will no longer recognize the given ID when passed to * utrans_open(). If the id is invalid then nothing is done. * * @param id a zero-terminated ID * @deprecated ICU 2.8 Use utrans_unregisterID() instead, see utrans.h */ U_DEPRECATED void U_EXPORT2 utrans_unregister(const char* id); /** * Deprecated, use utrans_openIDs() instead. * Return the ID of the index-th system transliterator. The result * is placed in the given buffer. If the given buffer is too small, * the initial substring is copied to buf. The result in buf is * always zero-terminated. * * @param index the number of the transliterator to return. Must * satisfy 0 <= index < utrans_countAvailableIDs(). If index is out * of range then it is treated as if it were 0. * @param buf the buffer in which to receive the ID. This may be * NULL, in which case no characters are copied. * @param bufCapacity the capacity of the buffer. Ignored if buf is * NULL. * @return the actual length of the index-th ID, not including * zero-termination. This may be greater than bufCapacity. * @deprecated ICU 2.8 Use utrans_openIDs() instead, see utrans.h */ U_DEPRECATED int32_t U_EXPORT2 utrans_getAvailableID(int32_t index, char* buf, int32_t bufCapacity); #endif /* #if !UCONFIG_NO_TRANSLITERATION */ #endif