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1 /*
2 **********************************************************************
3 *   Copyright (C) 2004-2010, International Business Machines
4 *   Corporation and others.  All Rights Reserved.
5 **********************************************************************
6 *   file name:  uregex.h
7 *   encoding:   US-ASCII
8 *   indentation:4
9 *
10 *   created on: 2004mar09
11 *   created by: Andy Heninger
12 *
13 *   ICU Regular Expressions, API for C
14 */
15 
16 /**
17  * \file
18  * \brief C API: Regular Expressions
19  *
20  * <p>This is a C wrapper around the C++ RegexPattern and RegexMatcher classes.</p>
21  */
22 
23 #ifndef UREGEX_H
24 #define UREGEX_H
25 
26 #include "unicode/utext.h"
27 #include "unicode/utypes.h"
28 
29 #if !UCONFIG_NO_REGULAR_EXPRESSIONS
30 
31 #include "unicode/localpointer.h"
32 #include "unicode/parseerr.h"
33 
34 struct URegularExpression;
35 /**
36   * Structure representing a compiled regular rexpression, plus the results
37   *    of a match operation.
38   * @stable ICU 3.0
39   */
40 typedef struct URegularExpression URegularExpression;
41 
42 
43 /**
44  * Constants for Regular Expression Match Modes.
45  * @stable ICU 2.4
46  */
47 typedef enum URegexpFlag{
48 
49 #ifndef U_HIDE_DRAFT_API
50     /** Forces normalization of pattern and strings.
51     Not implemented yet, just a placeholder, hence draft.
52     @draft ICU 2.4 */
53     UREGEX_CANON_EQ         = 128,
54 #endif
55     /**  Enable case insensitive matching.  @stable ICU 2.4 */
56     UREGEX_CASE_INSENSITIVE = 2,
57 
58     /**  Allow white space and comments within patterns  @stable ICU 2.4 */
59     UREGEX_COMMENTS         = 4,
60 
61     /**  If set, '.' matches line terminators,  otherwise '.' matching stops at line end.
62       *  @stable ICU 2.4 */
63     UREGEX_DOTALL           = 32,
64 
65     /**  If set, treat the entire pattern as a literal string.
66       *  Metacharacters or escape sequences in the input sequence will be given
67       *  no special meaning. Not implemented yet as of ICU 4.4.
68       *
69       *  The flags CASE_INSENSITIVE and UNICODE_CASE retain their impact
70       *  on matching when used in conjunction with this flag.
71       *  The other flags become superfluous.
72       *  TODO:  say which escapes are still handled; anything Java does
73       *         early (\\u) we should still do.
74       * @stable ICU 4.0
75       */
76     UREGEX_LITERAL = 16,
77 
78     /**   Control behavior of "$" and "^"
79       *    If set, recognize line terminators within string,
80       *    otherwise, match only at start and end of input string.
81       *   @stable ICU 2.4 */
82     UREGEX_MULTILINE        = 8,
83 
84     /**   Unix-only line endings.
85       *   When this mode is enabled, only \\u000a is recognized as a line ending
86       *    in the behavior of ., ^, and $.
87       *   @stable ICU 4.0
88       */
89     UREGEX_UNIX_LINES = 1,
90 
91     /**  Unicode word boundaries.
92       *     If set, \b uses the Unicode TR 29 definition of word boundaries.
93       *     Warning: Unicode word boundaries are quite different from
94       *     traditional regular expression word boundaries.  See
95       *     http://unicode.org/reports/tr29/#Word_Boundaries
96       *     @stable ICU 2.8
97       */
98     UREGEX_UWORD            = 256,
99 
100      /**  Error on Unrecognized backslash escapes.
101        *     If set, fail with an error on patterns that contain
102        *     backslash-escaped ASCII letters without a known specail
103        *     meaning.  If this flag is not set, these
104        *     escaped letters represent themselves.
105        *     @stable ICU 4.0
106        */
107      UREGEX_ERROR_ON_UNKNOWN_ESCAPES = 512
108 
109 }  URegexpFlag;
110 
111 /**
112   *  Open (compile) an ICU regular expression.  Compiles the regular expression in
113   *  string form into an internal representation using the specified match mode flags.
114   *  The resulting regular expression handle can then be used to perform various
115   *   matching operations.
116   *
117   *
118   * @param pattern        The Regular Expression pattern to be compiled.
119   * @param patternLength  The length of the pattern, or -1 if the pattern is
120   *                       NUL termintated.
121   * @param flags          Flags that alter the default matching behavior for
122   *                       the regular expression, UREGEX_CASE_INSENSITIVE, for
123   *                       example.  For default behavior, set this parameter to zero.
124   *                       See <code>enum URegexpFlag</code>.  All desired flags
125   *                       are bitwise-ORed together.
126   * @param pe             Receives the position (line and column nubers) of any syntax
127   *                       error within the source regular expression string.  If this
128   *                       information is not wanted, pass NULL for this parameter.
129   * @param status         Receives error detected by this function.
130   * @stable ICU 3.0
131   *
132   */
133 U_STABLE URegularExpression * U_EXPORT2
134 uregex_open( const  UChar          *pattern,
135                     int32_t         patternLength,
136                     uint32_t        flags,
137                     UParseError    *pe,
138                     UErrorCode     *status);
139 
140 /**
141   *  Open (compile) an ICU regular expression.  Compiles the regular expression in
142   *  string form into an internal representation using the specified match mode flags.
143   *  The resulting regular expression handle can then be used to perform various
144   *   matching operations.
145   *  <p>
146   *  The contents of the pattern UText will be extracted and saved. Ownership of the
147   *   UText struct itself remains with the caller. This is to match the behavior of
148   *   uregex_open().
149   *
150   * @param pattern        The Regular Expression pattern to be compiled.
151   * @param flags          Flags that alter the default matching behavior for
152   *                       the regular expression, UREGEX_CASE_INSENSITIVE, for
153   *                       example.  For default behavior, set this parameter to zero.
154   *                       See <code>enum URegexpFlag</code>.  All desired flags
155   *                       are bitwise-ORed together.
156   * @param pe             Receives the position (line and column nubers) of any syntax
157   *                       error within the source regular expression string.  If this
158   *                       information is not wanted, pass NULL for this parameter.
159   * @param status         Receives error detected by this function.
160   *
161   * @draft ICU 4.6
162   */
163 U_DRAFT URegularExpression *  U_EXPORT2
164 uregex_openUText(UText          *pattern,
165                  uint32_t        flags,
166                  UParseError    *pe,
167                  UErrorCode     *status);
168 
169 /**
170   *  Open (compile) an ICU regular expression.  The resulting regular expression
171   *   handle can then be used to perform various matching operations.
172   *  <p>
173   *   This function is the same as uregex_open, except that the pattern
174   *   is supplied as an 8 bit char * string in the default code page.
175   *
176   * @param pattern        The Regular Expression pattern to be compiled,
177   *                       NUL termintated.
178   * @param flags          Flags that alter the default matching behavior for
179   *                       the regular expression, UREGEX_CASE_INSENSITIVE, for
180   *                       example.  For default behavior, set this parameter to zero.
181   *                       See <code>enum URegexpFlag</code>.  All desired flags
182   *                       are bitwise-ORed together.
183   * @param pe             Receives the position (line and column nubers) of any syntax
184   *                       error within the source regular expression string.  If this
185   *                       information is not wanted, pass NULL for this parameter.
186   * @param status         Receives errors detected by this function.
187   * @return               The URegularExpression object representing the compiled
188   *                       pattern.
189   *
190   * @stable ICU 3.0
191   */
192 #if !UCONFIG_NO_CONVERSION
193 U_STABLE URegularExpression * U_EXPORT2
194 uregex_openC( const char           *pattern,
195                     uint32_t        flags,
196                     UParseError    *pe,
197                     UErrorCode     *status);
198 #endif
199 
200 
201 
202 /**
203   *  Close the regular expression, recovering all resources (memory) it
204   *   was holding.
205   *
206   * @param regexp   The regular expression to be closed.
207   * @stable ICU 3.0
208   */
209 U_STABLE void U_EXPORT2
210 uregex_close(URegularExpression *regexp);
211 
212 #if U_SHOW_CPLUSPLUS_API
213 
214 U_NAMESPACE_BEGIN
215 
216 /**
217  * \class LocalURegularExpressionPointer
218  * "Smart pointer" class, closes a URegularExpression via uregex_close().
219  * For most methods see the LocalPointerBase base class.
220  *
221  * @see LocalPointerBase
222  * @see LocalPointer
223  * @stable ICU 4.4
224  */
225 U_DEFINE_LOCAL_OPEN_POINTER(LocalURegularExpressionPointer, URegularExpression, uregex_close);
226 
227 U_NAMESPACE_END
228 
229 #endif
230 
231 /**
232  * Make a copy of a compiled regular expression.  Cloning a regular
233  * expression is faster than opening a second instance from the source
234  * form of the expression, and requires less memory.
235  * <p>
236  * Note that the current input string and the position of any matched text
237  *  within it are not cloned; only the pattern itself and and the
238  *  match mode flags are copied.
239  * <p>
240  * Cloning can be particularly useful to threaded applications that perform
241  * multiple match operations in parallel.  Each concurrent RE
242  * operation requires its own instance of a URegularExpression.
243  *
244  * @param regexp   The compiled regular expression to be cloned.
245  * @param status   Receives indication of any errors encountered
246  * @return the cloned copy of the compiled regular expression.
247  * @stable ICU 3.0
248  */
249 U_STABLE URegularExpression * U_EXPORT2
250 uregex_clone(const URegularExpression *regexp, UErrorCode *status);
251 
252 /**
253  *  Returns a pointer to the source form of the pattern for this regular expression.
254  *  This function will work even if the pattern was originally specified as a UText.
255  *
256  * @param regexp     The compiled regular expression.
257  * @param patLength  This output parameter will be set to the length of the
258  *                   pattern string.  A NULL pointer may be used here if the
259  *                   pattern length is not needed, as would be the case if
260  *                   the pattern is known in advance to be a NUL terminated
261  *                   string.
262  * @param status     Receives errors detected by this function.
263  * @return a pointer to the pattern string.  The storage for the string is
264  *                   owned by the regular expression object, and must not be
265  *                   altered or deleted by the application.  The returned string
266  *                   will remain valid until the regular expression is closed.
267  * @stable ICU 3.0
268  */
269 U_STABLE const UChar * U_EXPORT2
270 uregex_pattern(const URegularExpression *regexp,
271                      int32_t            *patLength,
272                      UErrorCode         *status);
273 
274 /**
275  *  Returns the source text of the pattern for this regular expression.
276  *  This function will work even if the pattern was originally specified as a UChar string.
277  *
278  * @param regexp     The compiled regular expression.
279  * @param status     Receives errors detected by this function.
280  * @return the pattern text.  The storage for the text is owned by the regular expression
281  *                   object, and must not be altered or deleted.
282  *
283  * @draft ICU 4.6
284  */
285 U_DRAFT UText * U_EXPORT2
286 uregex_patternUText(const URegularExpression *regexp,
287                           UErrorCode         *status);
288 
289 
290 /**
291   * Get the match mode flags that were specified when compiling this regular expression.
292   * @param status   Receives errors detected by this function.
293   * @param regexp   The compiled regular expression.
294   * @return         The match mode flags
295   * @see URegexpFlag
296   * @stable ICU 3.0
297   */
298 U_STABLE int32_t U_EXPORT2
299 uregex_flags(const  URegularExpression   *regexp,
300                     UErrorCode           *status);
301 
302 
303 /**
304   *  Set the subject text string upon which the regular expression will look for matches.
305   *  This function may be called any number of times, allowing the regular
306   *  expression pattern to be applied to different strings.
307   *  <p>
308   *  Regular expression matching operations work directly on the application's
309   *  string data.  No copy is made.  The subject string data must not be
310   *  altered after calling this function until after all regular expression
311   *  operations involving this string data are completed.
312   *  <p>
313   *  Zero length strings are permitted.  In this case, no subsequent match
314   *  operation will dereference the text string pointer.
315   *
316   * @param regexp     The compiled regular expression.
317   * @param text       The subject text string.
318   * @param textLength The length of the subject text, or -1 if the string
319   *                   is NUL terminated.
320   * @param status     Receives errors detected by this function.
321   * @stable ICU 3.0
322   */
323 U_STABLE void U_EXPORT2
324 uregex_setText(URegularExpression *regexp,
325                const UChar        *text,
326                int32_t             textLength,
327                UErrorCode         *status);
328 
329 
330 /**
331   *  Set the subject text string upon which the regular expression will look for matches.
332   *  This function may be called any number of times, allowing the regular
333   *  expression pattern to be applied to different strings.
334   *  <p>
335   *  Regular expression matching operations work directly on the application's
336   *  string data; only a shallow clone is made.  The subject string data must not be
337   *  altered after calling this function until after all regular expression
338   *  operations involving this string data are completed.
339   *
340   * @param regexp     The compiled regular expression.
341   * @param text       The subject text string.
342   * @param status     Receives errors detected by this function.
343   *
344   * @draft ICU 4.6
345   */
346 U_DRAFT void U_EXPORT2
347 uregex_setUText(URegularExpression *regexp,
348                 UText              *text,
349                 UErrorCode         *status);
350 
351 /**
352   *  Get the subject text that is currently associated with this
353   *   regular expression object.  If the input was supplied using uregex_setText(),
354   *   that pointer will be returned.  Otherwise, the characters in the input will
355   *   be extracted to a buffer and returned.  In either case, ownership remains
356   *   with the regular expression object.
357   *
358   *  This function will work even if the input was originally specified as a UText.
359   *
360   * @param regexp      The compiled regular expression.
361   * @param textLength  The length of the string is returned in this output parameter.
362   *                    A NULL pointer may be used here if the
363   *                    text length is not needed, as would be the case if
364   *                    the text is known in advance to be a NUL terminated
365   *                    string.
366   * @param status      Receives errors detected by this function.
367   * @return            Pointer to the subject text string currently associated with
368   *                    this regular expression.
369   * @stable ICU 3.0
370   */
371 U_STABLE const UChar * U_EXPORT2
372 uregex_getText(URegularExpression *regexp,
373                int32_t            *textLength,
374                UErrorCode         *status);
375 
376 
377 /**
378   *  Get the subject text that is currently associated with this
379   *   regular expression object.
380   *
381   *  This function will work even if the input was originally specified as a UChar string.
382   *
383   * @param regexp      The compiled regular expression.
384   * @param dest        A mutable UText in which to store the current input.
385   *                    If NULL, a new UText will be created as an immutable shallow clone
386   *                    of the actual input string.
387   * @param status      Receives errors detected by this function.
388   * @return            The subject text currently associated with this regular expression.
389   *                    If a pre-allocated UText was provided, it will always be used and returned.
390   *
391   * @draft ICU 4.6
392   */
393 U_DRAFT UText * U_EXPORT2
394 uregex_getUText(URegularExpression *regexp,
395                 UText              *dest,
396                 UErrorCode         *status);
397 
398 
399 /* BEGIN android-added
400    Removed it after Android upgrade to ICU4.6. */
401 /**
402   *  Set the subject text string upon which the regular expression is looking for matches
403   *  without changing any other aspect of the matching state.
404   *  The new and previous text strings must have the same content.
405   *
406   *  This function is intended for use in environments where ICU is operating on
407   *  strings that may move around in memory.  It provides a mechanism for notifying
408   *  ICU that the string has been relocated, and providing a new UText to access the
409   *  string in its new position.
410   *
411   *   Caution:  this function is normally used only by very specialized
412   *             system-level code.
413   *
414   * @param regexp     The compiled regular expression.
415   * @param text       The new (moved) text string.
416   * @param status     Receives errors detected by this function.
417   *
418   * @internal ICU 4.6
419   */
420 U_INTERNAL void U_EXPORT2
421 uregex_refreshUText(URegularExpression *regexp,
422                     UText              *text,
423                     UErrorCode         *status);
424 /* END android-added */
425 
426 /**
427   *   Attempts to match the input string against the pattern.
428   *   To succeed, the match must extend to the end of the string,
429   *   or cover the complete match region.
430   *
431   *   If startIndex >= zero the match operation starts at the specified
432   *   index and must extend to the end of the input string.  Any region
433   *   that has been specified is reset.
434   *
435   *   If startIndex == -1 the match must cover the input region, or the entire
436   *   input string if no region has been set.  This directly corresponds to
437   *   Matcher.matches() in Java
438   *
439   *    @param  regexp      The compiled regular expression.
440   *    @param  startIndex  The input string (native) index at which to begin matching, or -1
441   *                        to match the input Region.
442   *    @param  status      Receives errors detected by this function.
443   *    @return             TRUE if there is a match
444   *    @stable ICU 3.0
445   */
446 U_STABLE UBool U_EXPORT2
447 uregex_matches(URegularExpression *regexp,
448                 int32_t            startIndex,
449                 UErrorCode        *status);
450 
451 /**
452   *   64bit version of uregex_matches.
453   *   @draft ICU 4.6
454   */
455 U_DRAFT UBool U_EXPORT2
456 uregex_matches64(URegularExpression *regexp,
457                  int64_t            startIndex,
458                  UErrorCode        *status);
459 
460 /**
461   *   Attempts to match the input string, starting from the specified index, against the pattern.
462   *   The match may be of any length, and is not required to extend to the end
463   *   of the input string.  Contrast with uregex_matches().
464   *
465   *   <p>If startIndex is >= 0 any input region that was set for this
466   *   URegularExpression is reset before the operation begins.
467   *
468   *   <p>If the specified starting index == -1 the match begins at the start of the input
469   *   region, or at the start of the full string if no region has been specified.
470   *   This corresponds directly with Matcher.lookingAt() in Java.
471   *
472   *   <p>If the match succeeds then more information can be obtained via the
473   *    <code>uregexp_start()</code>, <code>uregexp_end()</code>,
474   *    and <code>uregexp_group()</code> functions.</p>
475   *
476   *    @param   regexp      The compiled regular expression.
477   *    @param   startIndex  The input string (native) index at which to begin matching, or
478   *                         -1 to match the Input Region
479   *    @param   status      A reference to a UErrorCode to receive any errors.
480   *    @return  TRUE if there is a match.
481   *    @stable ICU 3.0
482   */
483 U_STABLE UBool U_EXPORT2
484 uregex_lookingAt(URegularExpression *regexp,
485                  int32_t             startIndex,
486                  UErrorCode         *status);
487 
488 /**
489   *   64bit version of uregex_lookingAt.
490   *   @draft ICU 4.6
491   */
492 U_DRAFT UBool U_EXPORT2
493 uregex_lookingAt64(URegularExpression *regexp,
494                    int64_t             startIndex,
495                    UErrorCode         *status);
496 
497 /**
498   *   Find the first matching substring of the input string that matches the pattern.
499   *   If startIndex is >= zero the search for a match begins at the specified index,
500   *          and any match region is reset.  This corresponds directly with
501   *          Matcher.find(startIndex) in Java.
502   *
503   *   If startIndex == -1 the search begins at the start of the input region,
504   *           or at the start of the full string if no region has been specified.
505   *
506   *   If a match is found, <code>uregex_start(), uregex_end()</code>, and
507   *   <code>uregex_group()</code> will provide more information regarding the match.
508   *
509   *   @param   regexp      The compiled regular expression.
510   *   @param   startIndex  The position (native) in the input string to begin the search, or
511   *                        -1 to search within the Input Region.
512   *   @param   status      A reference to a UErrorCode to receive any errors.
513   *   @return              TRUE if a match is found.
514   *   @stable ICU 3.0
515   */
516 U_STABLE UBool U_EXPORT2
517 uregex_find(URegularExpression *regexp,
518             int32_t             startIndex,
519             UErrorCode         *status);
520 
521 /**
522   *   64bit version of uregex_find.
523   *   @draft ICU 4.6
524   */
525 U_DRAFT UBool U_EXPORT2
526 uregex_find64(URegularExpression *regexp,
527               int64_t             startIndex,
528               UErrorCode         *status);
529 
530 /**
531   *  Find the next pattern match in the input string.  Begin searching
532   *  the input at the location following the end of he previous match,
533   *  or at the start of the string (or region) if there is no
534   *  previous match.  If a match is found, <code>uregex_start(), uregex_end()</code>, and
535   *  <code>uregex_group()</code> will provide more information regarding the match.
536   *
537   *  @param   regexp      The compiled regular expression.
538   *  @param   status      A reference to a UErrorCode to receive any errors.
539   *  @return              TRUE if a match is found.
540   *  @see uregex_reset
541   *  @stable ICU 3.0
542   */
543 U_STABLE UBool U_EXPORT2
544 uregex_findNext(URegularExpression *regexp,
545                 UErrorCode         *status);
546 
547 /**
548   *   Get the number of capturing groups in this regular expression's pattern.
549   *   @param   regexp      The compiled regular expression.
550   *   @param   status      A reference to a UErrorCode to receive any errors.
551   *   @return the number of capture groups
552   *   @stable ICU 3.0
553   */
554 U_STABLE int32_t U_EXPORT2
555 uregex_groupCount(URegularExpression *regexp,
556                   UErrorCode         *status);
557 
558 /** Extract the string for the specified matching expression or subexpression.
559   * Group #0 is the complete string of matched text.
560   * Group #1 is the text matched by the first set of capturing parentheses.
561   *
562   *   @param   regexp       The compiled regular expression.
563   *   @param   groupNum     The capture group to extract.  Group 0 is the complete
564   *                         match.  The value of this parameter must be
565   *                         less than or equal to the number of capture groups in
566   *                         the pattern.
567   *   @param   dest         Buffer to receive the matching string data
568   *   @param   destCapacity Capacity of the dest buffer.
569   *   @param   status       A reference to a UErrorCode to receive any errors.
570   *   @return               Length of matching data,
571   *                         or -1 if no applicable match.
572   *   @stable ICU 3.0
573   */
574 U_STABLE int32_t U_EXPORT2
575 uregex_group(URegularExpression *regexp,
576              int32_t             groupNum,
577              UChar              *dest,
578              int32_t             destCapacity,
579              UErrorCode          *status);
580 
581 
582 /** Returns a shallow immutable clone of the entire input string.  The returned UText current native index
583   *   is set to the beginning of the requested capture group.  The capture group length is also
584   *   returned via groupLength.
585   * Group #0 is the complete string of matched text.
586   * Group #1 is the text matched by the first set of capturing parentheses.
587   *
588   *   @param   regexp       The compiled regular expression.
589   *   @param   groupNum     The capture group to extract.  Group 0 is the complete
590   *                         match.  The value of this parameter must be
591   *                         less than or equal to the number of capture groups in
592   *                         the pattern.
593   *   @param   dest         A mutable UText in which to store the current input.
594   *                         If NULL, a new UText will be created as an immutable shallow clone
595   *                         of the entire input string.
596   *   @param   groupLength  The group length of the desired capture group.
597   *   @param   status       A reference to a UErrorCode to receive any errors.
598   *   @return               The subject text currently associated with this regular expression.
599   *                         If a pre-allocated UText was provided, it will always be used and returned.
600 
601   *
602   *   @draft ICU 4.6
603   */
604 U_DRAFT UText * U_EXPORT2
605 uregex_groupUText(URegularExpression *regexp,
606                   int32_t             groupNum,
607                   UText              *dest,
608                   int64_t            *groupLength,
609                   UErrorCode         *status);
610 
611 
612 /** Extract the string for the specified matching expression or subexpression.
613   * Group #0 is the complete string of matched text.
614   * Group #1 is the text matched by the first set of capturing parentheses.
615   *
616   *   @param   regexp       The compiled regular expression.
617   *   @param   groupNum     The capture group to extract.  Group 0 is the complete
618   *                         match.  The value of this parameter must be
619   *                         less than or equal to the number of capture groups in
620   *                         the pattern.
621   *   @param   dest         Mutable UText to receive the matching string data.
622   *                         If NULL, a new UText will be created (which may not be mutable).
623   *   @param   status       A reference to a UErrorCode to receive any errors.
624   *   @return               The matching string data. If a pre-allocated UText was provided,
625   *                          it will always be used and returned.
626   *
627   *   @internal ICU 4.4 technology preview
628   */
629 U_INTERNAL UText * U_EXPORT2
630 uregex_groupUTextDeep(URegularExpression *regexp,
631                   int32_t             groupNum,
632                   UText              *dest,
633                   UErrorCode         *status);
634 
635 /**
636   *   Returns the index in the input string of the start of the text matched by the
637   *   specified capture group during the previous match operation.  Return -1 if
638   *   the capture group was not part of the last match.
639   *   Group #0 refers to the complete range of matched text.
640   *   Group #1 refers to the text matched by the first set of capturing parentheses.
641   *
642   *    @param   regexp      The compiled regular expression.
643   *    @param   groupNum    The capture group number
644   *    @param   status      A reference to a UErrorCode to receive any errors.
645   *    @return              the starting (native) position in the input of the text matched
646   *                         by the specified group.
647   *    @stable ICU 3.0
648   */
649 U_STABLE int32_t U_EXPORT2
650 uregex_start(URegularExpression *regexp,
651              int32_t             groupNum,
652              UErrorCode          *status);
653 
654 /**
655   *   64bit version of uregex_start.
656   *   @draft ICU 4.6
657   */
658 U_DRAFT int64_t U_EXPORT2
659 uregex_start64(URegularExpression *regexp,
660                int32_t             groupNum,
661                UErrorCode          *status);
662 
663 /**
664   *   Returns the index in the input string of the position following the end
665   *   of the text matched by the specified capture group.
666   *   Return -1 if the capture group was not part of the last match.
667   *   Group #0 refers to the complete range of matched text.
668   *   Group #1 refers to the text matched by the first set of capturing parentheses.
669   *
670   *    @param   regexp      The compiled regular expression.
671   *    @param   groupNum    The capture group number
672   *    @param   status      A reference to a UErrorCode to receive any errors.
673   *    @return              the (native) index of the position following the last matched character.
674   *    @stable ICU 3.0
675   */
676 U_STABLE int32_t U_EXPORT2
677 uregex_end(URegularExpression   *regexp,
678            int32_t               groupNum,
679            UErrorCode           *status);
680 
681 /**
682   *   64bit version of uregex_end.
683   *   @draft ICU 4.6
684   */
685 U_DRAFT int64_t U_EXPORT2
686 uregex_end64(URegularExpression *regexp,
687              int32_t               groupNum,
688              UErrorCode           *status);
689 
690 /**
691   *  Reset any saved state from the previous match.  Has the effect of
692   *  causing uregex_findNext to begin at the specified index, and causing
693   *  uregex_start(), uregex_end() and uregex_group() to return an error
694   *  indicating that there is no match information available.  Clears any
695   *  match region that may have been set.
696   *
697   *    @param   regexp      The compiled regular expression.
698   *    @param   index       The position (native) in the text at which a
699   *                         uregex_findNext() should begin searching.
700   *    @param   status      A reference to a UErrorCode to receive any errors.
701   *    @stable ICU 3.0
702   */
703 U_STABLE void U_EXPORT2
704 uregex_reset(URegularExpression    *regexp,
705              int32_t               index,
706              UErrorCode            *status);
707 
708 /**
709   *   64bit version of uregex_reset.
710   *   @draft ICU 4.6
711   */
712 U_DRAFT void U_EXPORT2
713 uregex_reset64(URegularExpression  *regexp,
714                int64_t               index,
715                UErrorCode            *status);
716 
717 /** Sets the limits of the matching region for this URegularExpression.
718   * The region is the part of the input string that will be considered when matching.
719   * Invoking this method resets any saved state from the previous match,
720   * then sets the region to start at the index specified by the start parameter
721   * and end at the index specified by the end parameter.
722   *
723   * Depending on the transparency and anchoring being used (see useTransparentBounds
724   * and useAnchoringBounds), certain constructs such as anchors may behave differently
725   * at or around the boundaries of the region
726   *
727   * The function will fail if start is greater than limit, or if either index
728   *  is less than zero or greater than the length of the string being matched.
729   *
730   * @param regexp The compiled regular expression.
731   * @param regionStart  The (native) index to begin searches at.
732   * @param regionLimit  The (native) index to end searches at (exclusive).
733   * @param status A pointer to a UErrorCode to receive any errors.
734   * @stable ICU 4.0
735   */
736 U_STABLE void U_EXPORT2
737 uregex_setRegion(URegularExpression   *regexp,
738                  int32_t               regionStart,
739                  int32_t               regionLimit,
740                  UErrorCode           *status);
741 
742 /**
743   *   64bit version of uregex_setRegion.
744   *   @draft ICU 4.6
745   */
746 U_DRAFT void U_EXPORT2
747 uregex_setRegion64(URegularExpression *regexp,
748                  int64_t               regionStart,
749                  int64_t               regionLimit,
750                  UErrorCode           *status);
751 
752 /**
753   *   Variation on uregex_setRegion to set the region without resetting the start index
754   *     without resetting the position for subsequent matches.
755   *   @draft ICU 4.6
756   */
757 U_DRAFT void U_EXPORT2
758 uregex_setRegionAndStart(URegularExpression *regexp,
759                  int64_t               regionStart,
760                  int64_t               regionLimit,
761                  int64_t               startIndex,
762                  UErrorCode           *status);
763 
764 /**
765   * Reports the start index of the matching region. Any matches found are limited to
766   * to the region bounded by regionStart (inclusive) and regionEnd (exclusive).
767   *
768   * @param regexp The compiled regular expression.
769   * @param status A pointer to a UErrorCode to receive any errors.
770   * @return The starting (native) index of this matcher's region.
771   * @stable ICU 4.0
772   */
773 U_STABLE int32_t U_EXPORT2
774 uregex_regionStart(const  URegularExpression   *regexp,
775                           UErrorCode           *status);
776 
777 /**
778   *   64bit version of uregex_regionStart.
779   *   @draft ICU 4.6
780   */
781 U_DRAFT int64_t U_EXPORT2
782 uregex_regionStart64(const  URegularExpression   *regexp,
783                             UErrorCode           *status);
784 
785 /**
786   * Reports the end index (exclusive) of the matching region for this URegularExpression.
787   * Any matches found are limited to to the region bounded by regionStart (inclusive)
788   * and regionEnd (exclusive).
789   *
790   * @param regexp The compiled regular expression.
791   * @param status A pointer to a UErrorCode to receive any errors.
792   * @return The ending point (native) of this matcher's region.
793   * @stable ICU 4.0
794   */
795 U_STABLE int32_t U_EXPORT2
796 uregex_regionEnd(const  URegularExpression   *regexp,
797                         UErrorCode           *status);
798 
799 /**
800   *   64bit version of uregex_regionEnd.
801   *   @draft ICU 4.6
802   */
803 U_DRAFT int64_t U_EXPORT2
804 uregex_regionEnd64(const  URegularExpression   *regexp,
805                           UErrorCode           *status);
806 
807 /**
808   * Queries the transparency of region bounds for this URegularExpression.
809   * See useTransparentBounds for a description of transparent and opaque bounds.
810   * By default, matching boundaries are opaque.
811   *
812   * @param regexp The compiled regular expression.
813   * @param status A pointer to a UErrorCode to receive any errors.
814   * @return TRUE if this matcher is using opaque bounds, false if it is not.
815   * @stable ICU 4.0
816   */
817 U_STABLE UBool U_EXPORT2
818 uregex_hasTransparentBounds(const  URegularExpression   *regexp,
819                                    UErrorCode           *status);
820 
821 
822 /**
823   * Sets the transparency of region bounds for this URegularExpression.
824   * Invoking this function with an argument of TRUE will set matches to use transparent bounds.
825   * If the boolean argument is FALSE, then opaque bounds will be used.
826   *
827   * Using transparent bounds, the boundaries of the matching region are transparent
828   * to lookahead, lookbehind, and boundary matching constructs. Those constructs can
829   * see text beyond the boundaries of the region while checking for a match.
830   *
831   * With opaque bounds, no text outside of the matching region is visible to lookahead,
832   * lookbehind, and boundary matching constructs.
833   *
834   * By default, opaque bounds are used.
835   *
836   * @param   regexp The compiled regular expression.
837   * @param   b      TRUE for transparent bounds; FALSE for opaque bounds
838   * @param   status A pointer to a UErrorCode to receive any errors.
839   * @stable ICU 4.0
840   **/
841 U_STABLE void U_EXPORT2
842 uregex_useTransparentBounds(URegularExpression   *regexp,
843                             UBool                b,
844                             UErrorCode           *status);
845 
846 
847 /**
848   * Return true if this URegularExpression is using anchoring bounds.
849   * By default, anchoring region bounds are used.
850   *
851   * @param  regexp The compiled regular expression.
852   * @param  status A pointer to a UErrorCode to receive any errors.
853   * @return TRUE if this matcher is using anchoring bounds.
854   * @stable ICU 4.0
855   */
856 U_STABLE UBool U_EXPORT2
857 uregex_hasAnchoringBounds(const  URegularExpression   *regexp,
858                                  UErrorCode           *status);
859 
860 
861 /**
862   * Set whether this URegularExpression is using Anchoring Bounds for its region.
863   * With anchoring bounds, pattern anchors such as ^ and $ will match at the start
864   * and end of the region.  Without Anchoring Bounds, anchors will only match at
865   * the positions they would in the complete text.
866   *
867   * Anchoring Bounds are the default for regions.
868   *
869   * @param regexp The compiled regular expression.
870   * @param b      TRUE if to enable anchoring bounds; FALSE to disable them.
871   * @param status A pointer to a UErrorCode to receive any errors.
872   * @stable ICU 4.0
873   */
874 U_STABLE void U_EXPORT2
875 uregex_useAnchoringBounds(URegularExpression   *regexp,
876                           UBool                 b,
877                           UErrorCode           *status);
878 
879 /**
880   * Return TRUE if the most recent matching operation touched the
881   *  end of the text being processed.  In this case, additional input text could
882   *  change the results of that match.
883   *
884   *  @param regexp The compiled regular expression.
885   *  @param status A pointer to a UErrorCode to receive any errors.
886   *  @return  TRUE if the most recent match hit the end of input
887   *  @stable ICU 4.0
888   */
889 U_STABLE UBool U_EXPORT2
890 uregex_hitEnd(const  URegularExpression   *regexp,
891                      UErrorCode           *status);
892 
893 /**
894   * Return TRUE the most recent match succeeded and additional input could cause
895   * it to fail. If this function returns false and a match was found, then more input
896   * might change the match but the match won't be lost. If a match was not found,
897   * then requireEnd has no meaning.
898   *
899   * @param regexp The compiled regular expression.
900   * @param status A pointer to a UErrorCode to receive any errors.
901   * @return TRUE  if more input could cause the most recent match to no longer match.
902   * @stable ICU 4.0
903   */
904 U_STABLE UBool U_EXPORT2
905 uregex_requireEnd(const  URegularExpression   *regexp,
906                          UErrorCode           *status);
907 
908 
909 
910 
911 
912 /**
913   *    Replaces every substring of the input that matches the pattern
914   *    with the given replacement string.  This is a convenience function that
915   *    provides a complete find-and-replace-all operation.
916   *
917   *    This method scans the input string looking for matches of the pattern.
918   *    Input that is not part of any match is copied unchanged to the
919   *    destination buffer.  Matched regions are replaced in the output
920   *    buffer by the replacement string.   The replacement string may contain
921   *    references to capture groups; these take the form of $1, $2, etc.
922   *
923   *    @param   regexp             The compiled regular expression.
924   *    @param   replacementText    A string containing the replacement text.
925   *    @param   replacementLength  The length of the replacement string, or
926   *                                -1 if it is NUL terminated.
927   *    @param   destBuf            A (UChar *) buffer that will receive the result.
928   *    @param   destCapacity       The capacity of the desitnation buffer.
929   *    @param   status             A reference to a UErrorCode to receive any errors.
930   *    @return                     The length of the string resulting from the find
931   *                                and replace operation.  In the event that the
932   *                                destination capacity is inadequate, the return value
933   *                                is still the full length of the untruncated string.
934   *    @stable ICU 3.0
935   */
936 U_STABLE int32_t U_EXPORT2
937 uregex_replaceAll(URegularExpression    *regexp,
938                   const UChar           *replacementText,
939                   int32_t                replacementLength,
940                   UChar                 *destBuf,
941                   int32_t                destCapacity,
942                   UErrorCode            *status);
943 
944 /**
945   *    Replaces every substring of the input that matches the pattern
946   *    with the given replacement string.  This is a convenience function that
947   *    provides a complete find-and-replace-all operation.
948   *
949   *    This method scans the input string looking for matches of the pattern.
950   *    Input that is not part of any match is copied unchanged to the
951   *    destination buffer.  Matched regions are replaced in the output
952   *    buffer by the replacement string.   The replacement string may contain
953   *    references to capture groups; these take the form of $1, $2, etc.
954   *
955   *    @param   regexp         The compiled regular expression.
956   *    @param   replacement    A string containing the replacement text.
957   *    @param   dest           A mutable UText that will receive the result.
958   *                             If NULL, a new UText will be created (which may not be mutable).
959   *    @param   status         A reference to a UErrorCode to receive any errors.
960   *    @return                 A UText containing the results of the find and replace.
961   *                             If a pre-allocated UText was provided, it will always be used and returned.
962   *
963   *    @draft ICU 4.6
964   */
965 U_DRAFT UText * U_EXPORT2
966 uregex_replaceAllUText(URegularExpression *regexp,
967                        UText              *replacement,
968                        UText              *dest,
969                        UErrorCode         *status);
970 
971 /**
972   *    Replaces the first substring of the input that matches the pattern
973   *    with the given replacement string.  This is a convenience function that
974   *    provides a complete find-and-replace operation.
975   *
976   *    This method scans the input string looking for a match of the pattern.
977   *    All input that is not part of the match is copied unchanged to the
978   *    destination buffer.  The matched region is replaced in the output
979   *    buffer by the replacement string.   The replacement string may contain
980   *    references to capture groups; these take the form of $1, $2, etc.
981   *
982   *    @param   regexp             The compiled regular expression.
983   *    @param   replacementText    A string containing the replacement text.
984   *    @param   replacementLength  The length of the replacement string, or
985   *                                -1 if it is NUL terminated.
986   *    @param   destBuf            A (UChar *) buffer that will receive the result.
987   *    @param   destCapacity       The capacity of the desitnation buffer.
988   *    @param   status             a reference to a UErrorCode to receive any errors.
989   *    @return                     The length of the string resulting from the find
990   *                                and replace operation.  In the event that the
991   *                                destination capacity is inadequate, the return value
992   *                                is still the full length of the untruncated string.
993   *    @stable ICU 3.0
994   */
995 U_STABLE int32_t U_EXPORT2
996 uregex_replaceFirst(URegularExpression  *regexp,
997                     const UChar         *replacementText,
998                     int32_t              replacementLength,
999                     UChar               *destBuf,
1000                     int32_t              destCapacity,
1001                     UErrorCode          *status);
1002 
1003 /**
1004   *    Replaces the first substring of the input that matches the pattern
1005   *    with the given replacement string.  This is a convenience function that
1006   *    provides a complete find-and-replace operation.
1007   *
1008   *    This method scans the input string looking for a match of the pattern.
1009   *    All input that is not part of the match is copied unchanged to the
1010   *    destination buffer.  The matched region is replaced in the output
1011   *    buffer by the replacement string.   The replacement string may contain
1012   *    references to capture groups; these take the form of $1, $2, etc.
1013   *
1014   *    @param   regexp         The compiled regular expression.
1015   *    @param   replacement    A string containing the replacement text.
1016   *    @param   dest           A mutable UText that will receive the result.
1017   *                             If NULL, a new UText will be created (which may not be mutable).
1018   *    @param   status         A reference to a UErrorCode to receive any errors.
1019   *    @return                 A UText containing the results of the find and replace.
1020   *                             If a pre-allocated UText was provided, it will always be used and returned.
1021   *
1022   *    @draft ICU 4.6
1023   */
1024 U_DRAFT UText * U_EXPORT2
1025 uregex_replaceFirstUText(URegularExpression *regexp,
1026                          UText              *replacement,
1027                          UText              *dest,
1028                          UErrorCode         *status);
1029 
1030 
1031 /**
1032   *   Implements a replace operation intended to be used as part of an
1033   *   incremental find-and-replace.
1034   *
1035   *   <p>The input string, starting from the end of the previous match and ending at
1036   *   the start of the current match, is appended to the destination string.  Then the
1037   *   replacement string is appended to the output string,
1038   *   including handling any substitutions of captured text.</p>
1039   *
1040   *   <p>A note on preflight computation of buffersize and error handling:
1041   *   Calls to uregex_appendReplacement() and uregex_appendTail() are
1042   *   designed to be chained, one after another, with the destination
1043   *   buffer pointer and buffer capacity updated after each in preparation
1044   *   to for the next.  If the destination buffer is exhausted partway through such a
1045   *   sequence, a U_BUFFER_OVERFLOW_ERROR status will be returned.  Normal
1046   *   ICU conventions are for a function to perform no action if it is
1047   *   called with an error status, but for this one case, uregex_appendRepacement()
1048   *   will operate normally so that buffer size computations will complete
1049   *   correctly.
1050   *
1051   *   <p>For simple, prepackaged, non-incremental find-and-replace
1052   *      operations, see replaceFirst() or replaceAll().</p>
1053   *
1054   *   @param   regexp      The regular expression object.
1055   *   @param   replacementText The string that will replace the matched portion of the
1056   *                        input string as it is copied to the destination buffer.
1057   *                        The replacement text may contain references ($1, for
1058   *                        example) to capture groups from the match.
1059   *   @param   replacementLength  The length of the replacement text string,
1060   *                        or -1 if the string is NUL terminated.
1061   *   @param   destBuf     The buffer into which the results of the
1062   *                        find-and-replace are placed.  On return, this pointer
1063   *                        will be updated to refer to the beginning of the
1064   *                        unused portion of buffer, leaving it in position for
1065   *                        a subsequent call to this function.
1066   *   @param   destCapacity The size of the output buffer,  On return, this
1067   *                        parameter will be updated to reflect the space remaining
1068   *                        unused in the output buffer.
1069   *   @param   status      A reference to a UErrorCode to receive any errors.
1070   *   @return              The length of the result string.  In the event that
1071   *                        destCapacity is inadequate, the full length of the
1072   *                        untruncated output string is returned.
1073   *
1074   *   @stable ICU 3.0
1075   *
1076   */
1077 U_STABLE int32_t U_EXPORT2
1078 uregex_appendReplacement(URegularExpression    *regexp,
1079                          const UChar           *replacementText,
1080                          int32_t                replacementLength,
1081                          UChar                **destBuf,
1082                          int32_t               *destCapacity,
1083                          UErrorCode            *status);
1084 
1085 
1086 /**
1087   *   Implements a replace operation intended to be used as part of an
1088   *   incremental find-and-replace.
1089   *
1090   *   <p>The input string, starting from the end of the previous match and ending at
1091   *   the start of the current match, is appended to the destination string.  Then the
1092   *   replacement string is appended to the output string,
1093   *   including handling any substitutions of captured text.</p>
1094   *
1095   *   <p>For simple, prepackaged, non-incremental find-and-replace
1096   *      operations, see replaceFirst() or replaceAll().</p>
1097   *
1098   *   @param   regexp      The regular expression object.
1099   *   @param   replacementText The string that will replace the matched portion of the
1100   *                        input string as it is copied to the destination buffer.
1101   *                        The replacement text may contain references ($1, for
1102   *                        example) to capture groups from the match.
1103   *   @param   dest        A mutable UText that will receive the result. Must not be NULL.
1104   *   @param   status      A reference to a UErrorCode to receive any errors.
1105   *
1106   *   @draft ICU 4.6
1107   */
1108 U_DRAFT void U_EXPORT2
1109 uregex_appendReplacementUText(URegularExpression    *regexp,
1110                               UText                 *replacementText,
1111                               UText                 *dest,
1112                               UErrorCode            *status);
1113 
1114 
1115 /**
1116   * As the final step in a find-and-replace operation, append the remainder
1117   * of the input string, starting at the position following the last match,
1118   * to the destination string. <code>uregex_appendTail()</code> is intended
1119   *  to be invoked after one or more invocations of the
1120   *  <code>uregex_appendReplacement()</code> function.
1121   *
1122   *   @param   regexp      The regular expression object.  This is needed to
1123   *                        obtain the input string and with the position
1124   *                        of the last match within it.
1125   *   @param   destBuf     The buffer in which the results of the
1126   *                        find-and-replace are placed.  On return, the pointer
1127   *                        will be updated to refer to the beginning of the
1128   *                        unused portion of buffer.
1129   *   @param   destCapacity The size of the output buffer,  On return, this
1130   *                        value will be updated to reflect the space remaining
1131   *                        unused in the output buffer.
1132   *   @param   status      A reference to a UErrorCode to receive any errors.
1133   *   @return              The length of the result string.  In the event that
1134   *                        destCapacity is inadequate, the full length of the
1135   *                        untruncated output string is returned.
1136   *
1137   *   @stable ICU 3.0
1138   */
1139 U_STABLE int32_t U_EXPORT2
1140 uregex_appendTail(URegularExpression    *regexp,
1141                   UChar                **destBuf,
1142                   int32_t               *destCapacity,
1143                   UErrorCode            *status);
1144 
1145 
1146 /**
1147   * As the final step in a find-and-replace operation, append the remainder
1148   * of the input string, starting at the position following the last match,
1149   * to the destination string. <code>uregex_appendTailUText()</code> is intended
1150   *  to be invoked after one or more invocations of the
1151   *  <code>uregex_appendReplacementUText()</code> function.
1152   *
1153   *   @param   regexp      The regular expression object.  This is needed to
1154   *                        obtain the input string and with the position
1155   *                        of the last match within it.
1156   *   @param   dest        A mutable UText that will receive the result. Must not be NULL.
1157   *   @return              The destination UText.
1158   *
1159   *   @draft ICU 4.6
1160   */
1161 U_DRAFT UText * U_EXPORT2
1162 uregex_appendTailUText(URegularExpression    *regexp,
1163                        UText                 *dest,
1164                        UErrorCode            *status);
1165 
1166 
1167 
1168  /**
1169    * Split a string into fields.  Somewhat like split() from Perl.
1170    *  The pattern matches identify delimiters that separate the input
1171    *  into fields.  The input data between the matches becomes the
1172    *  fields themselves.
1173    * <p>
1174    *  Each of the fields is copied from the input string to the destination
1175    *  buffer, and NUL terminated.  The position of each field within
1176    *  the destination buffer is returned in the destFields array.
1177    *
1178    *  Note:  another choice for the design of this function would be to not
1179    *         copy the resulting fields at all, but to return indexes and
1180    *         lengths within the source text.
1181    *           Advantages would be
1182    *             o  Faster.  No Copying.
1183    *             o  Nothing extra needed when field data may contain embedded NUL chars.
1184    *             o  Less memory needed if working on large data.
1185    *           Disadvantages
1186    *             o  Less consistent with C++ split, which copies into an
1187    *                array of UnicodeStrings.
1188    *             o  No NUL termination, extracted fields would be less convenient
1189    *                to use in most cases.
1190    *             o  Possible problems in the future, when support Unicode Normalization
1191    *                could cause the fields to not correspond exactly to
1192    *                a range of the source text.
1193    *
1194    *    @param   regexp      The compiled regular expression.
1195    *    @param   destBuf     A (UChar *) buffer to receive the fields that
1196    *                         are extracted from the input string. These
1197    *                         field pointers will refer to positions within the
1198    *                         destination buffer supplied by the caller.  Any
1199    *                         extra positions within the destFields array will be
1200    *                         set to NULL.
1201    *    @param   destCapacity The capacity of the destBuf.
1202    *    @param   requiredCapacity  The actual capacity required of the destBuf.
1203    *                         If destCapacity is too small, requiredCapacity will return
1204    *                         the total capacity required to hold all of the output, and
1205    *                         a U_BUFFER_OVERFLOW_ERROR will be returned.
1206    *    @param   destFields  An array to be filled with the position of each
1207    *                         of the extracted fields within destBuf.
1208    *    @param   destFieldsCapacity  The number of elements in the destFields array.
1209    *                If the number of fields found is less than destFieldsCapacity,
1210    *                the extra destFields elements are set to zero.
1211    *                If destFieldsCapacity is too small, the trailing part of the
1212    *                input, including any field delimiters, is treated as if it
1213    *                were the last field - it is copied to the destBuf, and
1214    *                its position is in the destBuf is stored in the last element
1215    *                of destFields.  This behavior mimics that of Perl.  It is not
1216    *                an error condition, and no error status is returned when all destField
1217    *                positions are used.
1218    * @param status  A reference to a UErrorCode to receive any errors.
1219    * @return        The number of fields into which the input string was split.
1220    * @stable ICU 3.0
1221    */
1222 U_STABLE int32_t U_EXPORT2
1223 uregex_split(   URegularExpression      *regexp,
1224                   UChar                 *destBuf,
1225                   int32_t                destCapacity,
1226                   int32_t               *requiredCapacity,
1227                   UChar                 *destFields[],
1228                   int32_t                destFieldsCapacity,
1229                   UErrorCode            *status);
1230 
1231 
1232   /**
1233    * Split a string into fields.  Somewhat like split() from Perl.
1234    * The pattern matches identify delimiters that separate the input
1235    *  into fields.  The input data between the matches becomes the
1236    *  fields themselves.
1237    * <p>
1238    * The behavior of this function is not very closely aligned with uregex_split();
1239    * instead, it is based on (and implemented directly on top of) the C++ split method.
1240    *
1241    * @param regexp  The compiled regular expression.
1242    * @param destFields    An array of mutable UText structs to receive the results of the split.
1243    *                If a field is NULL, a new UText is allocated to contain the results for
1244    *                that field. This new UText is not guaranteed to be mutable.
1245    * @param destFieldsCapacity  The number of elements in the destination array.
1246    *                If the number of fields found is less than destCapacity, the
1247    *                extra strings in the destination array are not altered.
1248    *                If the number of destination strings is less than the number
1249    *                of fields, the trailing part of the input string, including any
1250    *                field delimiters, is placed in the last destination string.
1251    *                This behavior mimics that of Perl.  It is not  an error condition, and no
1252    *                error status is returned when all destField positions are used.
1253    * @param status  A reference to a UErrorCode to receive any errors.
1254    * @return        The number of fields into which the input string was split.
1255    *
1256    * @draft ICU 4.6
1257    */
1258 U_DRAFT int32_t U_EXPORT2
1259 uregex_splitUText(URegularExpression    *regexp,
1260                   UText                 *destFields[],
1261                   int32_t                destFieldsCapacity,
1262                   UErrorCode            *status);
1263 
1264 
1265 
1266 
1267 /**
1268  * Set a processing time limit for match operations with this URegularExpression.
1269  *
1270  * Some patterns, when matching certain strings, can run in exponential time.
1271  * For practical purposes, the match operation may appear to be in an
1272  * infinite loop.
1273  * When a limit is set a match operation will fail with an error if the
1274  * limit is exceeded.
1275  * <p>
1276  * The units of the limit are steps of the match engine.
1277  * Correspondence with actual processor time will depend on the speed
1278  * of the processor and the details of the specific pattern, but will
1279  * typically be on the order of milliseconds.
1280  * <p>
1281  * By default, the matching time is not limited.
1282  * <p>
1283  *
1284  * @param   regexp      The compiled regular expression.
1285  * @param   limit       The limit value, or 0 for no limit.
1286  * @param   status      A reference to a UErrorCode to receive any errors.
1287  * @stable ICU 4.0
1288  */
1289 U_STABLE void U_EXPORT2
1290 uregex_setTimeLimit(URegularExpression      *regexp,
1291                     int32_t                  limit,
1292                     UErrorCode              *status);
1293 
1294 /**
1295  * Get the time limit for for matches with this URegularExpression.
1296  * A return value of zero indicates that there is no limit.
1297  *
1298  * @param   regexp      The compiled regular expression.
1299  * @param   status      A reference to a UErrorCode to receive any errors.
1300  * @return the maximum allowed time for a match, in units of processing steps.
1301  * @stable ICU 4.0
1302  */
1303 U_STABLE int32_t U_EXPORT2
1304 uregex_getTimeLimit(const URegularExpression      *regexp,
1305                           UErrorCode              *status);
1306 
1307 /**
1308  * Set the amount of heap storage avaliable for use by the match backtracking stack.
1309  * <p>
1310  * ICU uses a backtracking regular expression engine, with the backtrack stack
1311  * maintained on the heap.  This function sets the limit to the amount of memory
1312  * that can be used  for this purpose.  A backtracking stack overflow will
1313  * result in an error from the match operation that caused it.
1314  * <p>
1315  * A limit is desirable because a malicious or poorly designed pattern can use
1316  * excessive memory, potentially crashing the process.  A limit is enabled
1317  * by default.
1318  * <p>
1319  * @param   regexp      The compiled regular expression.
1320  * @param   limit       The maximum size, in bytes, of the matching backtrack stack.
1321  *                      A value of -1 means no limit.
1322  *                      The limit must be greater than zero, or -1.
1323  * @param   status      A reference to a UErrorCode to receive any errors.
1324  *
1325  * @stable ICU 4.0
1326  */
1327 U_STABLE void U_EXPORT2
1328 uregex_setStackLimit(URegularExpression      *regexp,
1329                      int32_t                  limit,
1330                      UErrorCode              *status);
1331 
1332 /**
1333  * Get the size of the heap storage available for use by the back tracking stack.
1334  *
1335  * @return  the maximum backtracking stack size, in bytes, or zero if the
1336  *          stack size is unlimited.
1337  * @stable ICU 4.0
1338  */
1339 U_STABLE int32_t U_EXPORT2
1340 uregex_getStackLimit(const URegularExpression      *regexp,
1341                            UErrorCode              *status);
1342 
1343 
1344 /**
1345  * Function pointer for a regular expression matching callback function.
1346  * When set, a callback function will be called periodically during matching
1347  * operations.  If the call back function returns FALSE, the matching
1348  * operation will be terminated early.
1349  *
1350  * Note:  the callback function must not call other functions on this
1351  *        URegularExpression.
1352  *
1353  * @param context  context pointer.  The callback function will be invoked
1354  *                 with the context specified at the time that
1355  *                 uregex_setMatchCallback() is called.
1356  * @param steps    the accumulated processing time, in match steps,
1357  *                 for this matching operation.
1358  * @return         TRUE to continue the matching operation.
1359  *                 FALSE to terminate the matching operation.
1360  * @stable ICU 4.0
1361  */
1362 U_CDECL_BEGIN
1363 typedef UBool U_CALLCONV URegexMatchCallback (
1364                    const void *context,
1365                    int32_t     steps);
1366 U_CDECL_END
1367 
1368 /**
1369  * Set a callback function for this URegularExpression.
1370  * During matching operations the function will be called periodically,
1371  * giving the application the opportunity to terminate a long-running
1372  * match.
1373  *
1374  * @param   regexp      The compiled regular expression.
1375  * @param   callback    A pointer to the user-supplied callback function.
1376  * @param   context     User context pointer.  The value supplied at the
1377  *                      time the callback function is set will be saved
1378  *                      and passed to the callback each time that it is called.
1379  * @param   status      A reference to a UErrorCode to receive any errors.
1380  * @stable ICU 4.0
1381  */
1382 U_STABLE void U_EXPORT2
1383 uregex_setMatchCallback(URegularExpression      *regexp,
1384                         URegexMatchCallback     *callback,
1385                         const void              *context,
1386                         UErrorCode              *status);
1387 
1388 
1389 /**
1390  *  Get the callback function for this URegularExpression.
1391  *
1392  * @param   regexp      The compiled regular expression.
1393  * @param   callback    Out paramater, receives a pointer to the user-supplied
1394  *                      callback function.
1395  * @param   context     Out parameter, receives the user context pointer that
1396  *                      was set when uregex_setMatchCallback() was called.
1397  * @param   status      A reference to a UErrorCode to receive any errors.
1398  * @stable ICU 4.0
1399  */
1400 U_STABLE void U_EXPORT2
1401 uregex_getMatchCallback(const URegularExpression    *regexp,
1402                         URegexMatchCallback        **callback,
1403                         const void                 **context,
1404                         UErrorCode                  *status);
1405 
1406 
1407 /**
1408  * Function pointer for a regular expression find callback function.
1409  *
1410  * When set, a callback function will be called during a find operation
1411  * and for operations that depend on find, such as findNext, split and some replace
1412  * operations like replaceFirst.
1413  * The callback will usually be called after each attempt at a match, but this is not a
1414  * guarantee that the callback will be invoked at each character.  For finds where the
1415  * match engine is invoked at each character, this may be close to true, but less likely
1416  * for more optimized loops where the pattern is known to only start, and the match
1417  * engine invoked, at certain characters.
1418  * When invoked, this callback will specify the index at which a match operation is about
1419  * to be attempted, giving the application the opportunity to terminate a long-running
1420  * find operation.
1421  *
1422  * If the call back function returns FALSE, the find operation will be terminated early.
1423  *
1424  * Note:  the callback function must not call other functions on this
1425  *        URegularExpression
1426  *
1427  * @param context  context pointer.  The callback function will be invoked
1428  *                 with the context specified at the time that
1429  *                 uregex_setFindProgressCallback() is called.
1430  * @param matchIndex  the next index at which a match attempt will be attempted for this
1431  *                 find operation.  If this callback interrupts the search, this is the
1432  *                 index at which a find/findNext operation may be re-initiated.
1433  * @return         TRUE to continue the matching operation.
1434  *                 FALSE to terminate the matching operation.
1435  * @draft ICU 4.6
1436  */
1437 U_CDECL_BEGIN
1438 typedef UBool U_CALLCONV URegexFindProgressCallback (
1439                    const void *context,
1440                    int64_t     matchIndex);
1441 U_CDECL_END
1442 
1443 /**
1444  *  Set the find progress callback function for this URegularExpression.
1445  *
1446  * @param   regexp      The compiled regular expression.
1447  * @param   callback    A pointer to the user-supplied callback function.
1448  * @param   context     User context pointer.  The value supplied at the
1449  *                      time the callback function is set will be saved
1450  *                      and passed to the callback each time that it is called.
1451  * @param   status      A reference to a UErrorCode to receive any errors.
1452  * @draft ICU 4.6
1453  */
1454 U_DRAFT void U_EXPORT2
1455 uregex_setFindProgressCallback(URegularExpression              *regexp,
1456                                 URegexFindProgressCallback      *callback,
1457                                 const void                      *context,
1458                                 UErrorCode                      *status);
1459 
1460 
1461 /**
1462  *  Get the find progress callback function for this URegularExpression.
1463  *
1464  * @param   regexp      The compiled regular expression.
1465  * @param   callback    Out paramater, receives a pointer to the user-supplied
1466  *                      callback function.
1467  * @param   context     Out parameter, receives the user context pointer that
1468  *                      was set when uregex_setFindProgressCallback() was called.
1469  * @param   status      A reference to a UErrorCode to receive any errors.
1470  * @draft ICU 4.6
1471  */
1472 U_DRAFT void U_EXPORT2
1473 uregex_getFindProgressCallback(const URegularExpression          *regexp,
1474                                 URegexFindProgressCallback        **callback,
1475                                 const void                        **context,
1476                                 UErrorCode                        *status);
1477 
1478 #endif   /*  !UCONFIG_NO_REGULAR_EXPRESSIONS  */
1479 #endif   /*  UREGEX_H  */
1480