1 /* 2 ****************************************************************************** 3 * Copyright (C) 1996-2015, International Business Machines Corporation and others. 4 * All Rights Reserved. 5 ****************************************************************************** 6 */ 7 8 #ifndef UBRK_H 9 #define UBRK_H 10 11 #include "unicode/utypes.h" 12 #include "unicode/uloc.h" 13 #include "unicode/utext.h" 14 #include "unicode/localpointer.h" 15 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 28 29 #if !UCONFIG_NO_BREAK_ITERATION 30 31 #include "unicode/parseerr.h" 32 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 * Note: The locale keyword "lb" can be used to modify line break 49 * behavior according to the CSS level 3 line-break options, see 50 * <http://dev.w3.org/csswg/css-text/#line-breaking>. For example: 51 * "ja@lb=strict", "zh@lb=loose". 52 * <p> 53 * Sentence boundary analysis allows selection with correct 54 * interpretation of periods within numbers and abbreviations, and 55 * trailing punctuation marks such as quotation marks and parentheses. 56 * <p> 57 * Note: The locale keyword "ss" can be used to enable use of 58 * segmentation suppression data (preventing breaks in English after 59 * abbreviations such as "Mr." or "Est.", for example), as follows: 60 * "en@ss=standard". 61 * <p> 62 * Word boundary analysis is used by search and replace functions, as 63 * well as within text editing applications that allow the user to 64 * select words with a double click. Word selection provides correct 65 * interpretation of punctuation marks within and following 66 * words. Characters that are not part of a word, such as symbols or 67 * punctuation marks, have word-breaks on both sides. 68 * <p> 69 * Character boundary analysis identifies the boundaries of 70 * "Extended Grapheme Clusters", which are groupings of codepoints 71 * that should be treated as character-like units for many text operations. 72 * Please see Unicode Standard Annex #29, Unicode Text Segmentation, 73 * http://www.unicode.org/reports/tr29/ for additional information 74 * on grapheme clusters and guidelines on their use. 75 * <p> 76 * Title boundary analysis locates all positions, 77 * typically starts of words, that should be set to Title Case 78 * when title casing the text. 79 * <p> 80 * The text boundary positions are found according to the rules 81 * described in Unicode Standard Annex #29, Text Boundaries, and 82 * Unicode Standard Annex #14, Line Breaking Properties. These 83 * are available at http://www.unicode.org/reports/tr14/ and 84 * http://www.unicode.org/reports/tr29/. 85 * <p> 86 * In addition to the plain C API defined in this header file, an 87 * object oriented C++ API with equivalent functionality is defined in the 88 * file brkiter.h. 89 * <p> 90 * Code snippets illustrating the use of the Break Iterator APIs 91 * are available in the ICU User Guide, 92 * http://icu-project.org/userguide/boundaryAnalysis.html 93 * and in the sample program icu/source/samples/break/break.cpp 94 */ 95 96 /** The possible types of text boundaries. @stable ICU 2.0 */ 97 typedef enum UBreakIteratorType { 98 /** Character breaks @stable ICU 2.0 */ 99 UBRK_CHARACTER = 0, 100 /** Word breaks @stable ICU 2.0 */ 101 UBRK_WORD = 1, 102 /** Line breaks @stable ICU 2.0 */ 103 UBRK_LINE = 2, 104 /** Sentence breaks @stable ICU 2.0 */ 105 UBRK_SENTENCE = 3, 106 107 #ifndef U_HIDE_DEPRECATED_API 108 /** 109 * Title Case breaks 110 * The iterator created using this type locates title boundaries as described for 111 * Unicode 3.2 only. For Unicode 4.0 and above title boundary iteration, 112 * please use Word Boundary iterator. 113 * 114 * @deprecated ICU 2.8 Use the word break iterator for titlecasing for Unicode 4 and later. 115 */ 116 UBRK_TITLE = 4, 117 #endif /* U_HIDE_DEPRECATED_API */ 118 UBRK_COUNT = 5 119 } UBreakIteratorType; 120 121 /** Value indicating all text boundaries have been returned. 122 * @stable ICU 2.0 123 */ 124 #define UBRK_DONE ((int32_t) -1) 125 126 127 /** 128 * Enum constants for the word break tags returned by 129 * getRuleStatus(). A range of values is defined for each category of 130 * word, to allow for further subdivisions of a category in future releases. 131 * Applications should check for tag values falling within the range, rather 132 * than for single individual values. 133 * @stable ICU 2.2 134 */ 135 typedef enum UWordBreak { 136 /** Tag value for "words" that do not fit into any of other categories. 137 * Includes spaces and most punctuation. */ 138 UBRK_WORD_NONE = 0, 139 /** Upper bound for tags for uncategorized words. */ 140 UBRK_WORD_NONE_LIMIT = 100, 141 /** Tag value for words that appear to be numbers, lower limit. */ 142 UBRK_WORD_NUMBER = 100, 143 /** Tag value for words that appear to be numbers, upper limit. */ 144 UBRK_WORD_NUMBER_LIMIT = 200, 145 /** Tag value for words that contain letters, excluding 146 * hiragana, katakana or ideographic characters, lower limit. */ 147 UBRK_WORD_LETTER = 200, 148 /** Tag value for words containing letters, upper limit */ 149 UBRK_WORD_LETTER_LIMIT = 300, 150 /** Tag value for words containing kana characters, lower limit */ 151 UBRK_WORD_KANA = 300, 152 /** Tag value for words containing kana characters, upper limit */ 153 UBRK_WORD_KANA_LIMIT = 400, 154 /** Tag value for words containing ideographic characters, lower limit */ 155 UBRK_WORD_IDEO = 400, 156 /** Tag value for words containing ideographic characters, upper limit */ 157 UBRK_WORD_IDEO_LIMIT = 500 158 } UWordBreak; 159 160 /** 161 * Enum constants for the line break tags returned by getRuleStatus(). 162 * A range of values is defined for each category of 163 * word, to allow for further subdivisions of a category in future releases. 164 * Applications should check for tag values falling within the range, rather 165 * than for single individual values. 166 * @stable ICU 2.8 167 */ 168 typedef enum ULineBreakTag { 169 /** Tag value for soft line breaks, positions at which a line break 170 * is acceptable but not required */ 171 UBRK_LINE_SOFT = 0, 172 /** Upper bound for soft line breaks. */ 173 UBRK_LINE_SOFT_LIMIT = 100, 174 /** Tag value for a hard, or mandatory line break */ 175 UBRK_LINE_HARD = 100, 176 /** Upper bound for hard line breaks. */ 177 UBRK_LINE_HARD_LIMIT = 200 178 } ULineBreakTag; 179 180 181 182 /** 183 * Enum constants for the sentence break tags returned by getRuleStatus(). 184 * A range of values is defined for each category of 185 * sentence, to allow for further subdivisions of a category in future releases. 186 * Applications should check for tag values falling within the range, rather 187 * than for single individual values. 188 * @stable ICU 2.8 189 */ 190 typedef enum USentenceBreakTag { 191 /** Tag value for for sentences ending with a sentence terminator 192 * ('.', '?', '!', etc.) character, possibly followed by a 193 * hard separator (CR, LF, PS, etc.) 194 */ 195 UBRK_SENTENCE_TERM = 0, 196 /** Upper bound for tags for sentences ended by sentence terminators. */ 197 UBRK_SENTENCE_TERM_LIMIT = 100, 198 /** Tag value for for sentences that do not contain an ending 199 * sentence terminator ('.', '?', '!', etc.) character, but 200 * are ended only by a hard separator (CR, LF, PS, etc.) or end of input. 201 */ 202 UBRK_SENTENCE_SEP = 100, 203 /** Upper bound for tags for sentences ended by a separator. */ 204 UBRK_SENTENCE_SEP_LIMIT = 200 205 /** Tag value for a hard, or mandatory line break */ 206 } USentenceBreakTag; 207 208 209 /** 210 * Open a new UBreakIterator for locating text boundaries for a specified locale. 211 * A UBreakIterator may be used for detecting character, line, word, 212 * and sentence breaks in text. 213 * @param type The type of UBreakIterator to open: one of UBRK_CHARACTER, UBRK_WORD, 214 * UBRK_LINE, UBRK_SENTENCE 215 * @param locale The locale specifying the text-breaking conventions. Note that 216 * locale keys such as "lb" and "ss" may be used to modify text break behavior, 217 * see general discussion of BreakIterator C API. 218 * @param text The text to be iterated over. 219 * @param textLength The number of characters in text, or -1 if null-terminated. 220 * @param status A UErrorCode to receive any errors. 221 * @return A UBreakIterator for the specified locale. 222 * @see ubrk_openRules 223 * @stable ICU 2.0 224 */ 225 U_STABLE UBreakIterator* U_EXPORT2 226 ubrk_open(UBreakIteratorType type, 227 const char *locale, 228 const UChar *text, 229 int32_t textLength, 230 UErrorCode *status); 231 232 /** 233 * Open a new UBreakIterator for locating text boundaries using specified breaking rules. 234 * The rule syntax is ... (TBD) 235 * @param rules A set of rules specifying the text breaking conventions. 236 * @param rulesLength The number of characters in rules, or -1 if null-terminated. 237 * @param text The text to be iterated over. May be null, in which case ubrk_setText() is 238 * used to specify the text to be iterated. 239 * @param textLength The number of characters in text, or -1 if null-terminated. 240 * @param parseErr Receives position and context information for any syntax errors 241 * detected while parsing the rules. 242 * @param status A UErrorCode to receive any errors. 243 * @return A UBreakIterator for the specified rules. 244 * @see ubrk_open 245 * @stable ICU 2.2 246 */ 247 U_STABLE UBreakIterator* U_EXPORT2 248 ubrk_openRules(const UChar *rules, 249 int32_t rulesLength, 250 const UChar *text, 251 int32_t textLength, 252 UParseError *parseErr, 253 UErrorCode *status); 254 255 /** 256 * Thread safe cloning operation 257 * @param bi iterator to be cloned 258 * @param stackBuffer <em>Deprecated functionality as of ICU 52, use NULL.</em><br> 259 * user allocated space for the new clone. If NULL new memory will be allocated. 260 * If buffer is not large enough, new memory will be allocated. 261 * Clients can use the U_BRK_SAFECLONE_BUFFERSIZE. 262 * @param pBufferSize <em>Deprecated functionality as of ICU 52, use NULL or 1.</em><br> 263 * pointer to size of allocated space. 264 * If *pBufferSize == 0, a sufficient size for use in cloning will 265 * be returned ('pre-flighting') 266 * If *pBufferSize is not enough for a stack-based safe clone, 267 * new memory will be allocated. 268 * @param status to indicate whether the operation went on smoothly or there were errors 269 * An informational status value, U_SAFECLONE_ALLOCATED_ERROR, is used if any allocations were necessary. 270 * @return pointer to the new clone 271 * @stable ICU 2.0 272 */ 273 U_STABLE UBreakIterator * U_EXPORT2 274 ubrk_safeClone( 275 const UBreakIterator *bi, 276 void *stackBuffer, 277 int32_t *pBufferSize, 278 UErrorCode *status); 279 280 #ifndef U_HIDE_DEPRECATED_API 281 282 /** 283 * A recommended size (in bytes) for the memory buffer to be passed to ubrk_saveClone(). 284 * @deprecated ICU 52. Do not rely on ubrk_safeClone() cloning into any provided buffer. 285 */ 286 #define U_BRK_SAFECLONE_BUFFERSIZE 1 287 288 #endif /* U_HIDE_DEPRECATED_API */ 289 290 /** 291 * Close a UBreakIterator. 292 * Once closed, a UBreakIterator may no longer be used. 293 * @param bi The break iterator to close. 294 * @stable ICU 2.0 295 */ 296 U_STABLE void U_EXPORT2 297 ubrk_close(UBreakIterator *bi); 298 299 #if U_SHOW_CPLUSPLUS_API 300 301 U_NAMESPACE_BEGIN 302 303 /** 304 * \class LocalUBreakIteratorPointer 305 * "Smart pointer" class, closes a UBreakIterator via ubrk_close(). 306 * For most methods see the LocalPointerBase base class. 307 * 308 * @see LocalPointerBase 309 * @see LocalPointer 310 * @stable ICU 4.4 311 */ 312 U_DEFINE_LOCAL_OPEN_POINTER(LocalUBreakIteratorPointer, UBreakIterator, ubrk_close); 313 314 U_NAMESPACE_END 315 316 #endif 317 318 /** 319 * Sets an existing iterator to point to a new piece of text 320 * @param bi The iterator to use 321 * @param text The text to be set 322 * @param textLength The length of the text 323 * @param status The error code 324 * @stable ICU 2.0 325 */ 326 U_STABLE void U_EXPORT2 327 ubrk_setText(UBreakIterator* bi, 328 const UChar* text, 329 int32_t textLength, 330 UErrorCode* status); 331 332 333 /** 334 * Sets an existing iterator to point to a new piece of text. 335 * 336 * All index positions returned by break iterator functions are 337 * native indices from the UText. For example, when breaking UTF-8 338 * encoded text, the break positions returned by \ref ubrk_next, \ref ubrk_previous, etc. 339 * will be UTF-8 string indices, not UTF-16 positions. 340 * 341 * @param bi The iterator to use 342 * @param text The text to be set. 343 * This function makes a shallow clone of the supplied UText. This means 344 * that the caller is free to immediately close or otherwise reuse the 345 * UText that was passed as a parameter, but that the underlying text itself 346 * must not be altered while being referenced by the break iterator. 347 * @param status The error code 348 * @stable ICU 3.4 349 */ 350 U_STABLE void U_EXPORT2 351 ubrk_setUText(UBreakIterator* bi, 352 UText* text, 353 UErrorCode* status); 354 355 356 357 /** 358 * Determine the most recently-returned text boundary. 359 * 360 * @param bi The break iterator to use. 361 * @return The character index most recently returned by \ref ubrk_next, \ref ubrk_previous, 362 * \ref ubrk_first, or \ref ubrk_last. 363 * @stable ICU 2.0 364 */ 365 U_STABLE int32_t U_EXPORT2 366 ubrk_current(const UBreakIterator *bi); 367 368 /** 369 * Advance the iterator to the boundary following the current boundary. 370 * 371 * @param bi The break iterator to use. 372 * @return The character index of the next text boundary, or UBRK_DONE 373 * if all text boundaries have been returned. 374 * @see ubrk_previous 375 * @stable ICU 2.0 376 */ 377 U_STABLE int32_t U_EXPORT2 378 ubrk_next(UBreakIterator *bi); 379 380 /** 381 * Set the iterator position to the boundary preceding the current boundary. 382 * 383 * @param bi The break iterator to use. 384 * @return The character index of the preceding text boundary, or UBRK_DONE 385 * if all text boundaries have been returned. 386 * @see ubrk_next 387 * @stable ICU 2.0 388 */ 389 U_STABLE int32_t U_EXPORT2 390 ubrk_previous(UBreakIterator *bi); 391 392 /** 393 * Set the iterator position to zero, the start of the text being scanned. 394 * @param bi The break iterator to use. 395 * @return The new iterator position (zero). 396 * @see ubrk_last 397 * @stable ICU 2.0 398 */ 399 U_STABLE int32_t U_EXPORT2 400 ubrk_first(UBreakIterator *bi); 401 402 /** 403 * Set the iterator position to the index immediately <EM>beyond</EM> the last character in the text being scanned. 404 * This is not the same as the last character. 405 * @param bi The break iterator to use. 406 * @return The character offset immediately <EM>beyond</EM> the last character in the 407 * text being scanned. 408 * @see ubrk_first 409 * @stable ICU 2.0 410 */ 411 U_STABLE int32_t U_EXPORT2 412 ubrk_last(UBreakIterator *bi); 413 414 /** 415 * Set the iterator position to the first boundary preceding the specified offset. 416 * The new position is always smaller than offset, or UBRK_DONE. 417 * @param bi The break iterator to use. 418 * @param offset The offset to begin scanning. 419 * @return The text boundary preceding offset, or UBRK_DONE. 420 * @see ubrk_following 421 * @stable ICU 2.0 422 */ 423 U_STABLE int32_t U_EXPORT2 424 ubrk_preceding(UBreakIterator *bi, 425 int32_t offset); 426 427 /** 428 * Advance the iterator to the first boundary following the specified offset. 429 * The value returned is always greater than offset, or UBRK_DONE. 430 * @param bi The break iterator to use. 431 * @param offset The offset to begin scanning. 432 * @return The text boundary following offset, or UBRK_DONE. 433 * @see ubrk_preceding 434 * @stable ICU 2.0 435 */ 436 U_STABLE int32_t U_EXPORT2 437 ubrk_following(UBreakIterator *bi, 438 int32_t offset); 439 440 /** 441 * Get a locale for which text breaking information is available. 442 * A UBreakIterator in a locale returned by this function will perform the correct 443 * text breaking for the locale. 444 * @param index The index of the desired locale. 445 * @return A locale for which number text breaking information is available, or 0 if none. 446 * @see ubrk_countAvailable 447 * @stable ICU 2.0 448 */ 449 U_STABLE const char* U_EXPORT2 450 ubrk_getAvailable(int32_t index); 451 452 /** 453 * Determine how many locales have text breaking information available. 454 * This function is most useful as determining the loop ending condition for 455 * calls to \ref ubrk_getAvailable. 456 * @return The number of locales for which text breaking information is available. 457 * @see ubrk_getAvailable 458 * @stable ICU 2.0 459 */ 460 U_STABLE int32_t U_EXPORT2 461 ubrk_countAvailable(void); 462 463 464 /** 465 * Returns true if the specfied position is a boundary position. As a side 466 * effect, leaves the iterator pointing to the first boundary position at 467 * or after "offset". 468 * @param bi The break iterator to use. 469 * @param offset the offset to check. 470 * @return True if "offset" is a boundary position. 471 * @stable ICU 2.0 472 */ 473 U_STABLE UBool U_EXPORT2 474 ubrk_isBoundary(UBreakIterator *bi, int32_t offset); 475 476 /** 477 * Return the status from the break rule that determined the most recently 478 * returned break position. The values appear in the rule source 479 * within brackets, {123}, for example. For rules that do not specify a 480 * status, a default value of 0 is returned. 481 * <p> 482 * For word break iterators, the possible values are defined in enum UWordBreak. 483 * @stable ICU 2.2 484 */ 485 U_STABLE int32_t U_EXPORT2 486 ubrk_getRuleStatus(UBreakIterator *bi); 487 488 /** 489 * Get the statuses from the break rules that determined the most recently 490 * returned break position. The values appear in the rule source 491 * within brackets, {123}, for example. The default status value for rules 492 * that do not explicitly provide one is zero. 493 * <p> 494 * For word break iterators, the possible values are defined in enum UWordBreak. 495 * @param bi The break iterator to use 496 * @param fillInVec an array to be filled in with the status values. 497 * @param capacity the length of the supplied vector. A length of zero causes 498 * the function to return the number of status values, in the 499 * normal way, without attemtping to store any values. 500 * @param status receives error codes. 501 * @return The number of rule status values from rules that determined 502 * the most recent boundary returned by the break iterator. 503 * @stable ICU 3.0 504 */ 505 U_STABLE int32_t U_EXPORT2 506 ubrk_getRuleStatusVec(UBreakIterator *bi, int32_t *fillInVec, int32_t capacity, UErrorCode *status); 507 508 /** 509 * Return the locale of the break iterator. You can choose between the valid and 510 * the actual locale. 511 * @param bi break iterator 512 * @param type locale type (valid or actual) 513 * @param status error code 514 * @return locale string 515 * @stable ICU 2.8 516 */ 517 U_STABLE const char* U_EXPORT2 518 ubrk_getLocaleByType(const UBreakIterator *bi, ULocDataLocaleType type, UErrorCode* status); 519 520 /** 521 * Set the subject text string upon which the break iterator is operating 522 * without changing any other aspect of the state. 523 * The new and previous text strings must have the same content. 524 * 525 * This function is intended for use in environments where ICU is operating on 526 * strings that may move around in memory. It provides a mechanism for notifying 527 * ICU that the string has been relocated, and providing a new UText to access the 528 * string in its new position. 529 * 530 * Note that the break iterator never copies the underlying text 531 * of a string being processed, but always operates directly on the original text 532 * provided by the user. Refreshing simply drops the references to the old text 533 * and replaces them with references to the new. 534 * 535 * Caution: this function is normally used only by very specialized 536 * system-level code. One example use case is with garbage collection 537 * that moves the text in memory. 538 * 539 * @param bi The break iterator. 540 * @param text The new (moved) text string. 541 * @param status Receives errors detected by this function. 542 * 543 * @stable ICU 49 544 */ 545 U_STABLE void U_EXPORT2 546 ubrk_refreshUText(UBreakIterator *bi, 547 UText *text, 548 UErrorCode *status); 549 550 #endif /* #if !UCONFIG_NO_BREAK_ITERATION */ 551 552 #endif 553