tor-browser

utrans.h (26157B)

---

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
*   Copyright (C) 1997-2011,2014-2015 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"
#include "unicode/uset.h"

#if U_SHOW_CPLUSPLUS_API
#include "unicode/localpointer.h"
#endif   // U_SHOW_CPLUSPLUS_API

/********************************************************************
* 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 &lt;source&gt; to &lt;target&gt; for a
    * transliterator with ID &lt;source&gt;-&lt;target&gt;.  For a transliterator
    * opened using a rule, it means forward direction rules, e.g.,
    * "A > B".
    */
   UTRANS_FORWARD,

   /**
    * UTRANS_REVERSE means from &lt;target&gt; to &lt;source&gt; for a
    * transliterator with ID &lt;source&gt;-&lt;target&gt;.  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 transliterated.
    * 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 transliterated.
    * 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_CAPI 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_CAPI 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_CAPI 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_CAPI void U_EXPORT2 
utrans_close(UTransliterator* trans);

#if U_SHOW_CPLUSPLUS_API

U_NAMESPACE_BEGIN

/**
* \class LocalUTransliteratorPointer
* "Smart pointer" class, closes a UTransliterator via utrans_close().
* For most methods see the LocalPointerBase base class.
*
* @see LocalPointerBase
* @see LocalPointer
* @stable ICU 4.4
*/
U_DEFINE_LOCAL_OPEN_POINTER(LocalUTransliteratorPointer, UTransliterator, utrans_close);

U_NAMESPACE_END

#endif

/**
* 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_CAPI 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_CAPI 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_CAPI 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_CAPI 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_CAPI 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_CAPI 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_CAPI void U_EXPORT2 
utrans_trans(const UTransliterator* trans,
            UReplaceable* rep,
            const UReplaceableCallbacks* repFunc,
            int32_t start,
            int32_t* limit,
            UErrorCode* status);

/**
* Transliterate the portion of the UReplaceable text buffer that can
* be transliterated unambiguously.  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_CAPI void U_EXPORT2 
utrans_transIncremental(const UTransliterator* trans,
                       UReplaceable* rep,
                       const 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 the length of the text buffer
* @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_CAPI 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 unambiguously.  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_CAPI void U_EXPORT2 
utrans_transIncrementalUChars(const UTransliterator* trans,
                             UChar* text,
                             int32_t* textLength,
                             int32_t textCapacity,
                             UTransPosition* pos,
                             UErrorCode* status);

/**
* Create a rule string that can be passed to utrans_openU to recreate this
* transliterator.
*
* @param trans     The transliterator
* @param escapeUnprintable if true then convert unprintable characters to their
*                  hex escape representations, \\uxxxx or \\Uxxxxxxxx.
*                  Unprintable characters are those other than
*                  U+000A, U+0020..U+007E.
* @param result    A pointer to a buffer to receive the rules.
* @param resultLength The maximum size of result.
* @param status    A pointer to the UErrorCode. In case of error status, the
*                  contents of result are undefined.
* @return int32_t   The length of the rule string (may be greater than resultLength,
*                  in which case an error is returned).
* @stable ICU 53
*/
U_CAPI int32_t U_EXPORT2
utrans_toRules(     const UTransliterator* trans,
                   UBool escapeUnprintable,
                   UChar* result, int32_t resultLength,
                   UErrorCode* status);

/**
* Returns the set of all characters that may be modified in the input text by
* this UTransliterator, optionally ignoring the transliterator's current filter.
* @param trans     The transliterator.
* @param ignoreFilter If false, the returned set incorporates the
*                  UTransliterator's current filter; if the filter is changed,
*                  the return value of this function will change. If true, the
*                  returned set ignores the effect of the UTransliterator's
*                  current filter.
* @param fillIn    Pointer to a USet object to receive the modifiable characters
*                  set. Previous contents of fillIn are lost. <em>If fillIn is
*                  NULL, then a new USet is created and returned. The caller
*                  owns the result and must dispose of it by calling uset_close.</em>
* @param status    A pointer to the UErrorCode.
* @return USet*    Either fillIn, or if fillIn is NULL, a pointer to a
*                  newly-allocated USet that the user must close. In case of
*                  error, NULL is returned.
* @stable ICU 53
*/
U_CAPI USet* U_EXPORT2
utrans_getSourceSet(const UTransliterator* trans,
                   UBool ignoreFilter,
                   USet* fillIn,
                   UErrorCode* status);

/* deprecated API ----------------------------------------------------------- */

#ifndef U_HIDE_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  /* U_HIDE_DEPRECATED_API */

#endif /* #if !UCONFIG_NO_TRANSLITERATION */

#endif