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Diffstat (limited to 'intl/icu/source/common/unicode/ubrk.h')
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diff --git a/intl/icu/source/common/unicode/ubrk.h b/intl/icu/source/common/unicode/ubrk.h new file mode 100644 index 000000000..f43943ed1 --- /dev/null +++ b/intl/icu/source/common/unicode/ubrk.h @@ -0,0 +1,571 @@ +// Copyright (C) 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +****************************************************************************** +* Copyright (C) 1996-2015, International Business Machines Corporation and others. +* All Rights Reserved. +****************************************************************************** +*/ + +#ifndef UBRK_H +#define UBRK_H + +#include "unicode/utypes.h" +#include "unicode/uloc.h" +#include "unicode/utext.h" +#include "unicode/localpointer.h" + +/** + * A text-break iterator. + * For usage in C programs. + */ +#ifndef UBRK_TYPEDEF_UBREAK_ITERATOR +# define UBRK_TYPEDEF_UBREAK_ITERATOR + /** + * Opaque type representing an ICU Break iterator object. + * @stable ICU 2.0 + */ + typedef struct UBreakIterator UBreakIterator; +#endif + +#if !UCONFIG_NO_BREAK_ITERATION + +#include "unicode/parseerr.h" + +/** + * \file + * \brief C API: BreakIterator + * + * <h2> BreakIterator C API </h2> + * + * The BreakIterator C API defines methods for finding the location + * of boundaries in text. Pointer to a UBreakIterator maintain a + * current position and scan over text returning the index of characters + * where boundaries occur. + * <p> + * Line boundary analysis determines where a text string can be broken + * when line-wrapping. The mechanism correctly handles punctuation and + * hyphenated words. + * <p> + * Note: The locale keyword "lb" can be used to modify line break + * behavior according to the CSS level 3 line-break options, see + * <http://dev.w3.org/csswg/css-text/#line-breaking>. For example: + * "ja@lb=strict", "zh@lb=loose". + * <p> + * Sentence boundary analysis allows selection with correct + * interpretation of periods within numbers and abbreviations, and + * trailing punctuation marks such as quotation marks and parentheses. + * <p> + * Note: The locale keyword "ss" can be used to enable use of + * segmentation suppression data (preventing breaks in English after + * abbreviations such as "Mr." or "Est.", for example), as follows: + * "en@ss=standard". + * <p> + * Word boundary analysis is used by search and replace functions, as + * well as within text editing applications that allow the user to + * select words with a double click. Word selection provides correct + * interpretation of punctuation marks within and following + * words. Characters that are not part of a word, such as symbols or + * punctuation marks, have word-breaks on both sides. + * <p> + * Character boundary analysis identifies the boundaries of + * "Extended Grapheme Clusters", which are groupings of codepoints + * that should be treated as character-like units for many text operations. + * Please see Unicode Standard Annex #29, Unicode Text Segmentation, + * http://www.unicode.org/reports/tr29/ for additional information + * on grapheme clusters and guidelines on their use. + * <p> + * Title boundary analysis locates all positions, + * typically starts of words, that should be set to Title Case + * when title casing the text. + * <p> + * The text boundary positions are found according to the rules + * described in Unicode Standard Annex #29, Text Boundaries, and + * Unicode Standard Annex #14, Line Breaking Properties. These + * are available at http://www.unicode.org/reports/tr14/ and + * http://www.unicode.org/reports/tr29/. + * <p> + * In addition to the plain C API defined in this header file, an + * object oriented C++ API with equivalent functionality is defined in the + * file brkiter.h. + * <p> + * Code snippets illustrating the use of the Break Iterator APIs + * are available in the ICU User Guide, + * http://icu-project.org/userguide/boundaryAnalysis.html + * and in the sample program icu/source/samples/break/break.cpp + */ + +/** The possible types of text boundaries. @stable ICU 2.0 */ +typedef enum UBreakIteratorType { + /** Character breaks @stable ICU 2.0 */ + UBRK_CHARACTER = 0, + /** Word breaks @stable ICU 2.0 */ + UBRK_WORD = 1, + /** Line breaks @stable ICU 2.0 */ + UBRK_LINE = 2, + /** Sentence breaks @stable ICU 2.0 */ + UBRK_SENTENCE = 3, + +#ifndef U_HIDE_DEPRECATED_API + /** + * Title Case breaks + * The iterator created using this type locates title boundaries as described for + * Unicode 3.2 only. For Unicode 4.0 and above title boundary iteration, + * please use Word Boundary iterator. + * + * @deprecated ICU 2.8 Use the word break iterator for titlecasing for Unicode 4 and later. + */ + UBRK_TITLE = 4, + /** + * One more than the highest normal UBreakIteratorType value. + * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420. + */ + UBRK_COUNT = 5 +#endif // U_HIDE_DEPRECATED_API +} UBreakIteratorType; + +/** Value indicating all text boundaries have been returned. + * @stable ICU 2.0 + */ +#define UBRK_DONE ((int32_t) -1) + + +/** + * Enum constants for the word break tags returned by + * getRuleStatus(). A range of values is defined for each category of + * word, to allow for further subdivisions of a category in future releases. + * Applications should check for tag values falling within the range, rather + * than for single individual values. + * + * The numeric values of all of these constants are stable (will not change). + * + * @stable ICU 2.2 +*/ +typedef enum UWordBreak { + /** Tag value for "words" that do not fit into any of other categories. + * Includes spaces and most punctuation. */ + UBRK_WORD_NONE = 0, + /** Upper bound for tags for uncategorized words. */ + UBRK_WORD_NONE_LIMIT = 100, + /** Tag value for words that appear to be numbers, lower limit. */ + UBRK_WORD_NUMBER = 100, + /** Tag value for words that appear to be numbers, upper limit. */ + UBRK_WORD_NUMBER_LIMIT = 200, + /** Tag value for words that contain letters, excluding + * hiragana, katakana or ideographic characters, lower limit. */ + UBRK_WORD_LETTER = 200, + /** Tag value for words containing letters, upper limit */ + UBRK_WORD_LETTER_LIMIT = 300, + /** Tag value for words containing kana characters, lower limit */ + UBRK_WORD_KANA = 300, + /** Tag value for words containing kana characters, upper limit */ + UBRK_WORD_KANA_LIMIT = 400, + /** Tag value for words containing ideographic characters, lower limit */ + UBRK_WORD_IDEO = 400, + /** Tag value for words containing ideographic characters, upper limit */ + UBRK_WORD_IDEO_LIMIT = 500 +} UWordBreak; + +/** + * Enum constants for the line break tags returned by getRuleStatus(). + * A range of values is defined for each category of + * word, to allow for further subdivisions of a category in future releases. + * Applications should check for tag values falling within the range, rather + * than for single individual values. + * + * The numeric values of all of these constants are stable (will not change). + * + * @stable ICU 2.8 +*/ +typedef enum ULineBreakTag { + /** Tag value for soft line breaks, positions at which a line break + * is acceptable but not required */ + UBRK_LINE_SOFT = 0, + /** Upper bound for soft line breaks. */ + UBRK_LINE_SOFT_LIMIT = 100, + /** Tag value for a hard, or mandatory line break */ + UBRK_LINE_HARD = 100, + /** Upper bound for hard line breaks. */ + UBRK_LINE_HARD_LIMIT = 200 +} ULineBreakTag; + + + +/** + * Enum constants for the sentence break tags returned by getRuleStatus(). + * A range of values is defined for each category of + * sentence, to allow for further subdivisions of a category in future releases. + * Applications should check for tag values falling within the range, rather + * than for single individual values. + * + * The numeric values of all of these constants are stable (will not change). + * + * @stable ICU 2.8 +*/ +typedef enum USentenceBreakTag { + /** Tag value for for sentences ending with a sentence terminator + * ('.', '?', '!', etc.) character, possibly followed by a + * hard separator (CR, LF, PS, etc.) + */ + UBRK_SENTENCE_TERM = 0, + /** Upper bound for tags for sentences ended by sentence terminators. */ + UBRK_SENTENCE_TERM_LIMIT = 100, + /** Tag value for for sentences that do not contain an ending + * sentence terminator ('.', '?', '!', etc.) character, but + * are ended only by a hard separator (CR, LF, PS, etc.) or end of input. + */ + UBRK_SENTENCE_SEP = 100, + /** Upper bound for tags for sentences ended by a separator. */ + UBRK_SENTENCE_SEP_LIMIT = 200 + /** Tag value for a hard, or mandatory line break */ +} USentenceBreakTag; + + +/** + * Open a new UBreakIterator for locating text boundaries for a specified locale. + * A UBreakIterator may be used for detecting character, line, word, + * and sentence breaks in text. + * @param type The type of UBreakIterator to open: one of UBRK_CHARACTER, UBRK_WORD, + * UBRK_LINE, UBRK_SENTENCE + * @param locale The locale specifying the text-breaking conventions. Note that + * locale keys such as "lb" and "ss" may be used to modify text break behavior, + * see general discussion of BreakIterator C API. + * @param text The text to be iterated over. + * @param textLength The number of characters in text, or -1 if null-terminated. + * @param status A UErrorCode to receive any errors. + * @return A UBreakIterator for the specified locale. + * @see ubrk_openRules + * @stable ICU 2.0 + */ +U_STABLE UBreakIterator* U_EXPORT2 +ubrk_open(UBreakIteratorType type, + const char *locale, + const UChar *text, + int32_t textLength, + UErrorCode *status); + +/** + * Open a new UBreakIterator for locating text boundaries using specified breaking rules. + * The rule syntax is ... (TBD) + * @param rules A set of rules specifying the text breaking conventions. + * @param rulesLength The number of characters in rules, or -1 if null-terminated. + * @param text The text to be iterated over. May be null, in which case ubrk_setText() is + * used to specify the text to be iterated. + * @param textLength The number of characters in text, or -1 if null-terminated. + * @param parseErr Receives position and context information for any syntax errors + * detected while parsing the rules. + * @param status A UErrorCode to receive any errors. + * @return A UBreakIterator for the specified rules. + * @see ubrk_open + * @stable ICU 2.2 + */ +U_STABLE UBreakIterator* U_EXPORT2 +ubrk_openRules(const UChar *rules, + int32_t rulesLength, + const UChar *text, + int32_t textLength, + UParseError *parseErr, + UErrorCode *status); + +/** + * Thread safe cloning operation + * @param bi iterator 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_BRK_SAFECLONE_BUFFERSIZE. + * @param pBufferSize <em>Deprecated functionality as of ICU 52, use NULL or 1.</em><br> + * pointer to size of allocated space. + * If *pBufferSize == 0, a sufficient size for use in cloning will + * be returned ('pre-flighting') + * If *pBufferSize is not enough for a stack-based safe clone, + * new memory will be allocated. + * @param status to indicate whether the operation went on smoothly or there were errors + * An informational status value, U_SAFECLONE_ALLOCATED_ERROR, is used if any allocations were necessary. + * @return pointer to the new clone + * @stable ICU 2.0 + */ +U_STABLE UBreakIterator * U_EXPORT2 +ubrk_safeClone( + const UBreakIterator *bi, + void *stackBuffer, + int32_t *pBufferSize, + UErrorCode *status); + +#ifndef U_HIDE_DEPRECATED_API + +/** + * A recommended size (in bytes) for the memory buffer to be passed to ubrk_saveClone(). + * @deprecated ICU 52. Do not rely on ubrk_safeClone() cloning into any provided buffer. + */ +#define U_BRK_SAFECLONE_BUFFERSIZE 1 + +#endif /* U_HIDE_DEPRECATED_API */ + +/** +* Close a UBreakIterator. +* Once closed, a UBreakIterator may no longer be used. +* @param bi The break iterator to close. + * @stable ICU 2.0 +*/ +U_STABLE void U_EXPORT2 +ubrk_close(UBreakIterator *bi); + +#if U_SHOW_CPLUSPLUS_API + +U_NAMESPACE_BEGIN + +/** + * \class LocalUBreakIteratorPointer + * "Smart pointer" class, closes a UBreakIterator via ubrk_close(). + * For most methods see the LocalPointerBase base class. + * + * @see LocalPointerBase + * @see LocalPointer + * @stable ICU 4.4 + */ +U_DEFINE_LOCAL_OPEN_POINTER(LocalUBreakIteratorPointer, UBreakIterator, ubrk_close); + +U_NAMESPACE_END + +#endif + +/** + * Sets an existing iterator to point to a new piece of text. + * The break iterator retains a pointer to the supplied text. + * The caller must not modify or delete the text while the BreakIterator + * retains the reference. + * + * @param bi The iterator to use + * @param text The text to be set + * @param textLength The length of the text + * @param status The error code + * @stable ICU 2.0 + */ +U_STABLE void U_EXPORT2 +ubrk_setText(UBreakIterator* bi, + const UChar* text, + int32_t textLength, + UErrorCode* status); + + +/** + * Sets an existing iterator to point to a new piece of text. + * + * All index positions returned by break iterator functions are + * native indices from the UText. For example, when breaking UTF-8 + * encoded text, the break positions returned by \ref ubrk_next, \ref ubrk_previous, etc. + * will be UTF-8 string indices, not UTF-16 positions. + * + * @param bi The iterator to use + * @param text The text to be set. + * This function makes a shallow clone of the supplied UText. This means + * that the caller is free to immediately close or otherwise reuse the + * UText that was passed as a parameter, but that the underlying text itself + * must not be altered while being referenced by the break iterator. + * @param status The error code + * @stable ICU 3.4 + */ +U_STABLE void U_EXPORT2 +ubrk_setUText(UBreakIterator* bi, + UText* text, + UErrorCode* status); + + + +/** + * Determine the most recently-returned text boundary. + * + * @param bi The break iterator to use. + * @return The character index most recently returned by \ref ubrk_next, \ref ubrk_previous, + * \ref ubrk_first, or \ref ubrk_last. + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_current(const UBreakIterator *bi); + +/** + * Advance the iterator to the boundary following the current boundary. + * + * @param bi The break iterator to use. + * @return The character index of the next text boundary, or UBRK_DONE + * if all text boundaries have been returned. + * @see ubrk_previous + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_next(UBreakIterator *bi); + +/** + * Set the iterator position to the boundary preceding the current boundary. + * + * @param bi The break iterator to use. + * @return The character index of the preceding text boundary, or UBRK_DONE + * if all text boundaries have been returned. + * @see ubrk_next + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_previous(UBreakIterator *bi); + +/** + * Set the iterator position to zero, the start of the text being scanned. + * @param bi The break iterator to use. + * @return The new iterator position (zero). + * @see ubrk_last + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_first(UBreakIterator *bi); + +/** + * Set the iterator position to the index immediately <EM>beyond</EM> the last character in the text being scanned. + * This is not the same as the last character. + * @param bi The break iterator to use. + * @return The character offset immediately <EM>beyond</EM> the last character in the + * text being scanned. + * @see ubrk_first + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_last(UBreakIterator *bi); + +/** + * Set the iterator position to the first boundary preceding the specified offset. + * The new position is always smaller than offset, or UBRK_DONE. + * @param bi The break iterator to use. + * @param offset The offset to begin scanning. + * @return The text boundary preceding offset, or UBRK_DONE. + * @see ubrk_following + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_preceding(UBreakIterator *bi, + int32_t offset); + +/** + * Advance the iterator to the first boundary following the specified offset. + * The value returned is always greater than offset, or UBRK_DONE. + * @param bi The break iterator to use. + * @param offset The offset to begin scanning. + * @return The text boundary following offset, or UBRK_DONE. + * @see ubrk_preceding + * @stable ICU 2.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_following(UBreakIterator *bi, + int32_t offset); + +/** +* Get a locale for which text breaking information is available. +* A UBreakIterator in a locale returned by this function will perform the correct +* text breaking for the locale. +* @param index The index of the desired locale. +* @return A locale for which number text breaking information is available, or 0 if none. +* @see ubrk_countAvailable +* @stable ICU 2.0 +*/ +U_STABLE const char* U_EXPORT2 +ubrk_getAvailable(int32_t index); + +/** +* Determine how many locales have text breaking information available. +* This function is most useful as determining the loop ending condition for +* calls to \ref ubrk_getAvailable. +* @return The number of locales for which text breaking information is available. +* @see ubrk_getAvailable +* @stable ICU 2.0 +*/ +U_STABLE int32_t U_EXPORT2 +ubrk_countAvailable(void); + + +/** +* Returns true if the specfied position is a boundary position. As a side +* effect, leaves the iterator pointing to the first boundary position at +* or after "offset". +* @param bi The break iterator to use. +* @param offset the offset to check. +* @return True if "offset" is a boundary position. +* @stable ICU 2.0 +*/ +U_STABLE UBool U_EXPORT2 +ubrk_isBoundary(UBreakIterator *bi, int32_t offset); + +/** + * Return the status from the break rule that determined the most recently + * returned break position. The values appear in the rule source + * within brackets, {123}, for example. For rules that do not specify a + * status, a default value of 0 is returned. + * <p> + * For word break iterators, the possible values are defined in enum UWordBreak. + * @stable ICU 2.2 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_getRuleStatus(UBreakIterator *bi); + +/** + * Get the statuses from the break rules that determined the most recently + * returned break position. The values appear in the rule source + * within brackets, {123}, for example. The default status value for rules + * that do not explicitly provide one is zero. + * <p> + * For word break iterators, the possible values are defined in enum UWordBreak. + * @param bi The break iterator to use + * @param fillInVec an array to be filled in with the status values. + * @param capacity the length of the supplied vector. A length of zero causes + * the function to return the number of status values, in the + * normal way, without attemtping to store any values. + * @param status receives error codes. + * @return The number of rule status values from rules that determined + * the most recent boundary returned by the break iterator. + * @stable ICU 3.0 + */ +U_STABLE int32_t U_EXPORT2 +ubrk_getRuleStatusVec(UBreakIterator *bi, int32_t *fillInVec, int32_t capacity, UErrorCode *status); + +/** + * Return the locale of the break iterator. You can choose between the valid and + * the actual locale. + * @param bi break iterator + * @param type locale type (valid or actual) + * @param status error code + * @return locale string + * @stable ICU 2.8 + */ +U_STABLE const char* U_EXPORT2 +ubrk_getLocaleByType(const UBreakIterator *bi, ULocDataLocaleType type, UErrorCode* status); + +/** + * Set the subject text string upon which the break iterator is operating + * without changing any other aspect of the state. + * The new and previous text strings must have the same content. + * + * This function is intended for use in environments where ICU is operating on + * strings that may move around in memory. It provides a mechanism for notifying + * ICU that the string has been relocated, and providing a new UText to access the + * string in its new position. + * + * Note that the break iterator never copies the underlying text + * of a string being processed, but always operates directly on the original text + * provided by the user. Refreshing simply drops the references to the old text + * and replaces them with references to the new. + * + * Caution: this function is normally used only by very specialized + * system-level code. One example use case is with garbage collection + * that moves the text in memory. + * + * @param bi The break iterator. + * @param text The new (moved) text string. + * @param status Receives errors detected by this function. + * + * @stable ICU 49 + */ +U_STABLE void U_EXPORT2 +ubrk_refreshUText(UBreakIterator *bi, + UText *text, + UErrorCode *status); + +#endif /* #if !UCONFIG_NO_BREAK_ITERATION */ + +#endif |