intl/icu/source/common/unicode/ubrk.h

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /*
     2 ******************************************************************************
     3 * Copyright (C) 1996-2013, International Business Machines Corporation and others.
     4 * All Rights Reserved.
     5 ******************************************************************************
     6 */
     8 #ifndef UBRK_H
     9 #define UBRK_H
    11 #include "unicode/utypes.h"
    12 #include "unicode/uloc.h"
    13 #include "unicode/utext.h"
    14 #include "unicode/localpointer.h"
    16 /**
    17  * A text-break iterator.
    18  *  For usage in C programs.
    19  */
    20 #ifndef UBRK_TYPEDEF_UBREAK_ITERATOR
    21 #   define UBRK_TYPEDEF_UBREAK_ITERATOR
    22     /**
    23      *  Opaque type representing an ICU Break iterator object.
    24      *  @stable ICU 2.0
    25      */
    26     typedef struct UBreakIterator UBreakIterator;
    27 #endif
    29 #if !UCONFIG_NO_BREAK_ITERATION
    31 #include "unicode/parseerr.h"
    33 /**
    34  * \file
    35  * \brief C API: BreakIterator
    36  *
    37  * <h2> BreakIterator C API </h2>
    38  *
    39  * The BreakIterator C API defines  methods for finding the location
    40  * of boundaries in text. Pointer to a UBreakIterator maintain a
    41  * current position and scan over text returning the index of characters
    42  * where boundaries occur.
    43  * <p>
    44  * Line boundary analysis determines where a text string can be broken
    45  * when line-wrapping. The mechanism correctly handles punctuation and
    46  * hyphenated words.
    47  * <p>
    48  * Sentence boundary analysis allows selection with correct
    49  * interpretation of periods within numbers and abbreviations, and
    50  * trailing punctuation marks such as quotation marks and parentheses.
    51  * <p>
    52  * Word boundary analysis is used by search and replace functions, as
    53  * well as within text editing applications that allow the user to
    54  * select words with a double click. Word selection provides correct
    55  * interpretation of punctuation marks within and following
    56  * words. Characters that are not part of a word, such as symbols or
    57  * punctuation marks, have word-breaks on both sides.
    58  * <p>
    59  * Character boundary analysis identifies the boundaries of
    60  * "Extended Grapheme Clusters", which are groupings of codepoints
    61  * that should be treated as character-like units for many text operations.
    62  * Please see Unicode Standard Annex #29, Unicode Text Segmentation,
    63  * http://www.unicode.org/reports/tr29/ for additional information 
    64  * on grapheme clusters and guidelines on their use.
    65  * <p>
    66  * Title boundary analysis locates all positions,
    67  * typically starts of words, that should be set to Title Case
    68  * when title casing the text.
    69  * <p>
    70  * The text boundary positions are found according to the rules
    71  * described in Unicode Standard Annex #29, Text Boundaries, and
    72  * Unicode Standard Annex #14, Line Breaking Properties.  These
    73  * are available at http://www.unicode.org/reports/tr14/ and
    74  * http://www.unicode.org/reports/tr29/.
    75  * <p>
    76  * In addition to the plain C API defined in this header file, an
    77  * object oriented C++ API with equivalent functionality is defined in the
    78  * file brkiter.h.
    79  * <p>
    80  * Code snippets illustrating the use of the Break Iterator APIs
    81  * are available in the ICU User Guide,
    82  * http://icu-project.org/userguide/boundaryAnalysis.html
    83  * and in the sample program icu/source/samples/break/break.cpp
    84  */
    86 /** The possible types of text boundaries.  @stable ICU 2.0 */
    87 typedef enum UBreakIteratorType {
    88   /** Character breaks  @stable ICU 2.0 */
    89   UBRK_CHARACTER = 0,
    90   /** Word breaks @stable ICU 2.0 */
    91   UBRK_WORD = 1,
    92   /** Line breaks @stable ICU 2.0 */
    93   UBRK_LINE = 2,
    94   /** Sentence breaks @stable ICU 2.0 */
    95   UBRK_SENTENCE = 3,
    97 #ifndef U_HIDE_DEPRECATED_API
    98   /**
    99    * Title Case breaks
   100    * The iterator created using this type locates title boundaries as described for
   101    * Unicode 3.2 only. For Unicode 4.0 and above title boundary iteration,
   102    * please use Word Boundary iterator.
   103    *
   104    * @deprecated ICU 2.8 Use the word break iterator for titlecasing for Unicode 4 and later.
   105    */
   106   UBRK_TITLE = 4,
   107 #endif /* U_HIDE_DEPRECATED_API */
   108   UBRK_COUNT = 5
   109 } UBreakIteratorType;
   111 /** Value indicating all text boundaries have been returned.
   112  *  @stable ICU 2.0
   113  */
   114 #define UBRK_DONE ((int32_t) -1)
   117 /**
   118  *  Enum constants for the word break tags returned by
   119  *  getRuleStatus().  A range of values is defined for each category of
   120  *  word, to allow for further subdivisions of a category in future releases.
   121  *  Applications should check for tag values falling within the range, rather
   122  *  than for single individual values.
   123  *  @stable ICU 2.2
   124 */
   125 typedef enum UWordBreak {
   126     /** Tag value for "words" that do not fit into any of other categories.
   127      *  Includes spaces and most punctuation. */
   128     UBRK_WORD_NONE           = 0,
   129     /** Upper bound for tags for uncategorized words. */
   130     UBRK_WORD_NONE_LIMIT     = 100,
   131     /** Tag value for words that appear to be numbers, lower limit.    */
   132     UBRK_WORD_NUMBER         = 100,
   133     /** Tag value for words that appear to be numbers, upper limit.    */
   134     UBRK_WORD_NUMBER_LIMIT   = 200,
   135     /** Tag value for words that contain letters, excluding
   136      *  hiragana, katakana or ideographic characters, lower limit.    */
   137     UBRK_WORD_LETTER         = 200,
   138     /** Tag value for words containing letters, upper limit  */
   139     UBRK_WORD_LETTER_LIMIT   = 300,
   140     /** Tag value for words containing kana characters, lower limit */
   141     UBRK_WORD_KANA           = 300,
   142     /** Tag value for words containing kana characters, upper limit */
   143     UBRK_WORD_KANA_LIMIT     = 400,
   144     /** Tag value for words containing ideographic characters, lower limit */
   145     UBRK_WORD_IDEO           = 400,
   146     /** Tag value for words containing ideographic characters, upper limit */
   147     UBRK_WORD_IDEO_LIMIT     = 500
   148 } UWordBreak;
   150 /**
   151  *  Enum constants for the line break tags returned by getRuleStatus().
   152  *  A range of values is defined for each category of
   153  *  word, to allow for further subdivisions of a category in future releases.
   154  *  Applications should check for tag values falling within the range, rather
   155  *  than for single individual values.
   156  *  @stable ICU 2.8
   157 */
   158 typedef enum ULineBreakTag {
   159     /** Tag value for soft line breaks, positions at which a line break
   160       *  is acceptable but not required                */
   161     UBRK_LINE_SOFT            = 0,
   162     /** Upper bound for soft line breaks.              */
   163     UBRK_LINE_SOFT_LIMIT      = 100,
   164     /** Tag value for a hard, or mandatory line break  */
   165     UBRK_LINE_HARD            = 100,
   166     /** Upper bound for hard line breaks.              */
   167     UBRK_LINE_HARD_LIMIT      = 200
   168 } ULineBreakTag;
   172 /**
   173  *  Enum constants for the sentence break tags returned by getRuleStatus().
   174  *  A range of values is defined for each category of
   175  *  sentence, to allow for further subdivisions of a category in future releases.
   176  *  Applications should check for tag values falling within the range, rather
   177  *  than for single individual values.
   178  *  @stable ICU 2.8
   179 */
   180 typedef enum USentenceBreakTag {
   181     /** Tag value for for sentences  ending with a sentence terminator
   182       * ('.', '?', '!', etc.) character, possibly followed by a
   183       * hard separator (CR, LF, PS, etc.)
   184       */
   185     UBRK_SENTENCE_TERM       = 0,
   186     /** Upper bound for tags for sentences ended by sentence terminators.    */
   187     UBRK_SENTENCE_TERM_LIMIT = 100,
   188     /** Tag value for for sentences that do not contain an ending
   189       * sentence terminator ('.', '?', '!', etc.) character, but
   190       * are ended only by a hard separator (CR, LF, PS, etc.) or end of input.
   191       */
   192     UBRK_SENTENCE_SEP        = 100,
   193     /** Upper bound for tags for sentences ended by a separator.              */
   194     UBRK_SENTENCE_SEP_LIMIT  = 200
   195     /** Tag value for a hard, or mandatory line break  */
   196 } USentenceBreakTag;
   199 /**
   200  * Open a new UBreakIterator for locating text boundaries for a specified locale.
   201  * A UBreakIterator may be used for detecting character, line, word,
   202  * and sentence breaks in text.
   203  * @param type The type of UBreakIterator to open: one of UBRK_CHARACTER, UBRK_WORD,
   204  * UBRK_LINE, UBRK_SENTENCE
   205  * @param locale The locale specifying the text-breaking conventions.
   206  * @param text The text to be iterated over.
   207  * @param textLength The number of characters in text, or -1 if null-terminated.
   208  * @param status A UErrorCode to receive any errors.
   209  * @return A UBreakIterator for the specified locale.
   210  * @see ubrk_openRules
   211  * @stable ICU 2.0
   212  */
   213 U_STABLE UBreakIterator* U_EXPORT2
   214 ubrk_open(UBreakIteratorType type,
   215       const char *locale,
   216       const UChar *text,
   217       int32_t textLength,
   218       UErrorCode *status);
   220 /**
   221  * Open a new UBreakIterator for locating text boundaries using specified breaking rules.
   222  * The rule syntax is ... (TBD)
   223  * @param rules A set of rules specifying the text breaking conventions.
   224  * @param rulesLength The number of characters in rules, or -1 if null-terminated.
   225  * @param text The text to be iterated over.  May be null, in which case ubrk_setText() is
   226  *        used to specify the text to be iterated.
   227  * @param textLength The number of characters in text, or -1 if null-terminated.
   228  * @param parseErr   Receives position and context information for any syntax errors
   229  *                   detected while parsing the rules.
   230  * @param status A UErrorCode to receive any errors.
   231  * @return A UBreakIterator for the specified rules.
   232  * @see ubrk_open
   233  * @stable ICU 2.2
   234  */
   235 U_STABLE UBreakIterator* U_EXPORT2
   236 ubrk_openRules(const UChar     *rules,
   237                int32_t         rulesLength,
   238                const UChar     *text,
   239                int32_t          textLength,
   240                UParseError     *parseErr,
   241                UErrorCode      *status);
   243 /**
   244  * Thread safe cloning operation
   245  * @param bi iterator to be cloned
   246  * @param stackBuffer <em>Deprecated functionality as of ICU 52, use NULL.</em><br>
   247  *  user allocated space for the new clone. If NULL new memory will be allocated.
   248  *  If buffer is not large enough, new memory will be allocated.
   249  *  Clients can use the U_BRK_SAFECLONE_BUFFERSIZE.
   250  * @param pBufferSize <em>Deprecated functionality as of ICU 52, use NULL or 1.</em><br>
   251  *  pointer to size of allocated space.
   252  *  If *pBufferSize == 0, a sufficient size for use in cloning will
   253  *  be returned ('pre-flighting')
   254  *  If *pBufferSize is not enough for a stack-based safe clone,
   255  *  new memory will be allocated.
   256  * @param status to indicate whether the operation went on smoothly or there were errors
   257  *  An informational status value, U_SAFECLONE_ALLOCATED_ERROR, is used if any allocations were necessary.
   258  * @return pointer to the new clone
   259  * @stable ICU 2.0
   260  */
   261 U_STABLE UBreakIterator * U_EXPORT2
   262 ubrk_safeClone(
   263           const UBreakIterator *bi,
   264           void *stackBuffer,
   265           int32_t *pBufferSize,
   266           UErrorCode *status);
   268 #ifndef U_HIDE_DEPRECATED_API
   270 /**
   271   * A recommended size (in bytes) for the memory buffer to be passed to ubrk_saveClone().
   272   * @deprecated ICU 52. Do not rely on ubrk_safeClone() cloning into any provided buffer.
   273   */
   274 #define U_BRK_SAFECLONE_BUFFERSIZE 1
   276 #endif /* U_HIDE_DEPRECATED_API */
   278 /**
   279 * Close a UBreakIterator.
   280 * Once closed, a UBreakIterator may no longer be used.
   281 * @param bi The break iterator to close.
   282  * @stable ICU 2.0
   283 */
   284 U_STABLE void U_EXPORT2
   285 ubrk_close(UBreakIterator *bi);
   287 #if U_SHOW_CPLUSPLUS_API
   289 U_NAMESPACE_BEGIN
   291 /**
   292  * \class LocalUBreakIteratorPointer
   293  * "Smart pointer" class, closes a UBreakIterator via ubrk_close().
   294  * For most methods see the LocalPointerBase base class.
   295  *
   296  * @see LocalPointerBase
   297  * @see LocalPointer
   298  * @stable ICU 4.4
   299  */
   300 U_DEFINE_LOCAL_OPEN_POINTER(LocalUBreakIteratorPointer, UBreakIterator, ubrk_close);
   302 U_NAMESPACE_END
   304 #endif
   306 /**
   307  * Sets an existing iterator to point to a new piece of text
   308  * @param bi The iterator to use
   309  * @param text The text to be set
   310  * @param textLength The length of the text
   311  * @param status The error code
   312  * @stable ICU 2.0
   313  */
   314 U_STABLE void U_EXPORT2
   315 ubrk_setText(UBreakIterator* bi,
   316              const UChar*    text,
   317              int32_t         textLength,
   318              UErrorCode*     status);
   321 /**
   322  * Sets an existing iterator to point to a new piece of text.
   323  *
   324  * All index positions returned by break iterator functions are
   325  * native indices from the UText. For example, when breaking UTF-8
   326  * encoded text, the break positions returned by \ref ubrk_next, \ref ubrk_previous, etc.
   327  * will be UTF-8 string indices, not UTF-16 positions.
   328  *
   329  * @param bi The iterator to use
   330  * @param text The text to be set.
   331  *             This function makes a shallow clone of the supplied UText.  This means
   332  *             that the caller is free to immediately close or otherwise reuse the
   333  *             UText that was passed as a parameter, but that the underlying text itself
   334  *             must not be altered while being referenced by the break iterator.
   335  * @param status The error code
   336  * @stable ICU 3.4
   337  */
   338 U_STABLE void U_EXPORT2
   339 ubrk_setUText(UBreakIterator* bi,
   340              UText*          text,
   341              UErrorCode*     status);
   345 /**
   346  * Determine the most recently-returned text boundary.
   347  *
   348  * @param bi The break iterator to use.
   349  * @return The character index most recently returned by \ref ubrk_next, \ref ubrk_previous,
   350  * \ref ubrk_first, or \ref ubrk_last.
   351  * @stable ICU 2.0
   352  */
   353 U_STABLE int32_t U_EXPORT2
   354 ubrk_current(const UBreakIterator *bi);
   356 /**
   357  * Advance the iterator to the boundary following the current boundary.
   358  *
   359  * @param bi The break iterator to use.
   360  * @return The character index of the next text boundary, or UBRK_DONE
   361  * if all text boundaries have been returned.
   362  * @see ubrk_previous
   363  * @stable ICU 2.0
   364  */
   365 U_STABLE int32_t U_EXPORT2
   366 ubrk_next(UBreakIterator *bi);
   368 /**
   369  * Set the iterator position to the boundary preceding the current boundary.
   370  *
   371  * @param bi The break iterator to use.
   372  * @return The character index of the preceding text boundary, or UBRK_DONE
   373  * if all text boundaries have been returned.
   374  * @see ubrk_next
   375  * @stable ICU 2.0
   376  */
   377 U_STABLE int32_t U_EXPORT2
   378 ubrk_previous(UBreakIterator *bi);
   380 /**
   381  * Set the iterator position to the index of the first character in the text being scanned.
   382  * This is not always the same as index 0 of the text.
   383  * @param bi The break iterator to use.
   384  * @return The character index of the first character in the text being scanned.
   385  * @see ubrk_last
   386  * @stable ICU 2.0
   387  */
   388 U_STABLE int32_t U_EXPORT2
   389 ubrk_first(UBreakIterator *bi);
   391 /**
   392  * Set the iterator position to the index immediately <EM>beyond</EM> the last character in the text being scanned.
   393  * This is not the same as the last character.
   394  * @param bi The break iterator to use.
   395  * @return The character offset immediately <EM>beyond</EM> the last character in the
   396  * text being scanned.
   397  * @see ubrk_first
   398  * @stable ICU 2.0
   399  */
   400 U_STABLE int32_t U_EXPORT2
   401 ubrk_last(UBreakIterator *bi);
   403 /**
   404  * Set the iterator position to the first boundary preceding the specified offset.
   405  * The new position is always smaller than offset, or UBRK_DONE.
   406  * @param bi The break iterator to use.
   407  * @param offset The offset to begin scanning.
   408  * @return The text boundary preceding offset, or UBRK_DONE.
   409  * @see ubrk_following
   410  * @stable ICU 2.0
   411  */
   412 U_STABLE int32_t U_EXPORT2
   413 ubrk_preceding(UBreakIterator *bi,
   414            int32_t offset);
   416 /**
   417  * Advance the iterator to the first boundary following the specified offset.
   418  * The value returned is always greater than offset, or UBRK_DONE.
   419  * @param bi The break iterator to use.
   420  * @param offset The offset to begin scanning.
   421  * @return The text boundary following offset, or UBRK_DONE.
   422  * @see ubrk_preceding
   423  * @stable ICU 2.0
   424  */
   425 U_STABLE int32_t U_EXPORT2
   426 ubrk_following(UBreakIterator *bi,
   427            int32_t offset);
   429 /**
   430 * Get a locale for which text breaking information is available.
   431 * A UBreakIterator in a locale returned by this function will perform the correct
   432 * text breaking for the locale.
   433 * @param index The index of the desired locale.
   434 * @return A locale for which number text breaking information is available, or 0 if none.
   435 * @see ubrk_countAvailable
   436 * @stable ICU 2.0
   437 */
   438 U_STABLE const char* U_EXPORT2
   439 ubrk_getAvailable(int32_t index);
   441 /**
   442 * Determine how many locales have text breaking information available.
   443 * This function is most useful as determining the loop ending condition for
   444 * calls to \ref ubrk_getAvailable.
   445 * @return The number of locales for which text breaking information is available.
   446 * @see ubrk_getAvailable
   447 * @stable ICU 2.0
   448 */
   449 U_STABLE int32_t U_EXPORT2
   450 ubrk_countAvailable(void);
   453 /**
   454 * Returns true if the specfied position is a boundary position.  As a side
   455 * effect, leaves the iterator pointing to the first boundary position at
   456 * or after "offset".
   457 * @param bi The break iterator to use.
   458 * @param offset the offset to check.
   459 * @return True if "offset" is a boundary position.
   460 * @stable ICU 2.0
   461 */
   462 U_STABLE  UBool U_EXPORT2
   463 ubrk_isBoundary(UBreakIterator *bi, int32_t offset);
   465 /**
   466  * Return the status from the break rule that determined the most recently
   467  * returned break position.  The values appear in the rule source
   468  * within brackets, {123}, for example.  For rules that do not specify a
   469  * status, a default value of 0 is returned.
   470  * <p>
   471  * For word break iterators, the possible values are defined in enum UWordBreak.
   472  * @stable ICU 2.2
   473  */
   474 U_STABLE  int32_t U_EXPORT2
   475 ubrk_getRuleStatus(UBreakIterator *bi);
   477 /**
   478  * Get the statuses from the break rules that determined the most recently
   479  * returned break position.  The values appear in the rule source
   480  * within brackets, {123}, for example.  The default status value for rules
   481  * that do not explicitly provide one is zero.
   482  * <p>
   483  * For word break iterators, the possible values are defined in enum UWordBreak.
   484  * @param bi        The break iterator to use
   485  * @param fillInVec an array to be filled in with the status values.
   486  * @param capacity  the length of the supplied vector.  A length of zero causes
   487  *                  the function to return the number of status values, in the
   488  *                  normal way, without attemtping to store any values.
   489  * @param status    receives error codes.
   490  * @return          The number of rule status values from rules that determined
   491  *                  the most recent boundary returned by the break iterator.
   492  * @stable ICU 3.0
   493  */
   494 U_STABLE  int32_t U_EXPORT2
   495 ubrk_getRuleStatusVec(UBreakIterator *bi, int32_t *fillInVec, int32_t capacity, UErrorCode *status);
   497 /**
   498  * Return the locale of the break iterator. You can choose between the valid and
   499  * the actual locale.
   500  * @param bi break iterator
   501  * @param type locale type (valid or actual)
   502  * @param status error code
   503  * @return locale string
   504  * @stable ICU 2.8
   505  */
   506 U_STABLE const char* U_EXPORT2
   507 ubrk_getLocaleByType(const UBreakIterator *bi, ULocDataLocaleType type, UErrorCode* status);
   509 /**
   510   *  Set the subject text string upon which the break iterator is operating
   511   *  without changing any other aspect of the state.
   512   *  The new and previous text strings must have the same content.
   513   *
   514   *  This function is intended for use in environments where ICU is operating on
   515   *  strings that may move around in memory.  It provides a mechanism for notifying
   516   *  ICU that the string has been relocated, and providing a new UText to access the
   517   *  string in its new position.
   518   *
   519   *  Note that the break iterator never copies the underlying text
   520   *  of a string being processed, but always operates directly on the original text
   521   *  provided by the user. Refreshing simply drops the references to the old text
   522   *  and replaces them with references to the new.
   523   *
   524   *  Caution:  this function is normally used only by very specialized
   525   *            system-level code.   One example use case is with garbage collection
   526   *            that moves the text in memory.
   527   *
   528   * @param bi         The break iterator.
   529   * @param text       The new (moved) text string.
   530   * @param status     Receives errors detected by this function.
   531   *
   532   * @stable ICU 49
   533   */
   534 U_STABLE void U_EXPORT2
   535 ubrk_refreshUText(UBreakIterator *bi,
   536                        UText          *text,
   537                        UErrorCode     *status);
   539 #endif /* #if !UCONFIG_NO_BREAK_ITERATION */
   541 #endif

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