/usr/include/unicode/uregex.h (43948B)
This is a C wrapper around the C++ RegexPattern and RegexMatcher classes.
*/ #ifndef UREGEX_H #define UREGEX_H #include "unicode/utypes.h" #if !UCONFIG_NO_REGULAR_EXPRESSIONS #include "unicode/parseerr.h" struct URegularExpression; /** * Structure representing a compiled regular rexpression, plus the results * of a match operation. * @stable ICU 3.0 */ typedef struct URegularExpression URegularExpression; /** * Constants for Regular Expression Match Modes. * @stable ICU 2.4 */ typedef enum URegexpFlag{ #ifndef U_HIDE_DRAFT_API /** Forces normalization of pattern and strings. Not implemented yet, just a placeholder, hence draft. @draft ICU 2.4 */ UREGEX_CANON_EQ = 128, #endif /** Enable case insensitive matching. @stable ICU 2.4 */ UREGEX_CASE_INSENSITIVE = 2, /** Allow white space and comments within patterns @stable ICU 2.4 */ UREGEX_COMMENTS = 4, /** If set, '.' matches line terminators, otherwise '.' matching stops at line end. * @stable ICU 2.4 */ UREGEX_DOTALL = 32, /** If set, treat the entire pattern as a literal string. * Metacharacters or escape sequences in the input sequence will be given * no special meaning. * * The flags CASE_INSENSITIVE and UNICODE_CASE retain their impact * on matching when used in conjunction with this flag. * The other flags become superfluous. * TODO: say which escapes are still handled; anything Java does * early (\\u) we should still do. * @stable ICU 4.0 */ UREGEX_LITERAL = 16, /** Control behavior of "$" and "^" * If set, recognize line terminators within string, * otherwise, match only at start and end of input string. * @stable ICU 2.4 */ UREGEX_MULTILINE = 8, /** Unix-only line endings. * When this mode is enabled, only \\u000a is recognized as a line ending * in the behavior of ., ^, and $. * @stable ICU 4.0 */ UREGEX_UNIX_LINES = 1, /** Unicode word boundaries. * If set, \b uses the Unicode TR 29 definition of word boundaries. * Warning: Unicode word boundaries are quite different from * traditional regular expression word boundaries. See * http://unicode.org/reports/tr29/#Word_Boundaries * @stable ICU 2.8 */ UREGEX_UWORD = 256, /** Error on Unrecognized backslash escapes. * If set, fail with an error on patterns that contain * backslash-escaped ASCII letters without a known specail * meaning. If this flag is not set, these * escaped letters represent themselves. * @stable ICU 4.0 */ UREGEX_ERROR_ON_UNKNOWN_ESCAPES = 512 } URegexpFlag; /** * Open (compile) an ICU regular expression. Compiles the regular expression in * string form into an internal representation using the specified match mode flags. * The resulting regular expression handle can then be used to perform various * matching operations. * * @param pattern The Regular Expression pattern to be compiled. * @param patternLength The length of the pattern, or -1 if the pattern is * NUL termintated. * @param flags Flags that alter the default matching behavior for * the regular expression, UREGEX_CASE_INSENSITIVE, for * example. For default behavior, set this parameter to zero. * Seeenum URegexpFlag. All desired flags
* are bitwise-ORed together.
* @param pe Receives the position (line and column nubers) of any syntax
* error within the source regular expression string. If this
* information is not wanted, pass NULL for this parameter.
* @param status Receives error detected by this function.
* @stable ICU 3.0
*
*/
U_STABLE URegularExpression * U_EXPORT2
uregex_open( const UChar *pattern,
int32_t patternLength,
uint32_t flags,
UParseError *pe,
UErrorCode *status);
/**
* Open (compile) an ICU regular expression. The resulting regular expression
* handle can then be used to perform various matching operations.
*
* This function is the same as uregex_open, except that the pattern
* is supplied as an 8 bit char * string in the default code page.
*
* @param pattern The Regular Expression pattern to be compiled,
* NUL termintated.
* @param flags Flags that alter the default matching behavior for
* the regular expression, UREGEX_CASE_INSENSITIVE, for
* example. For default behavior, set this parameter to zero.
* See enum URegexpFlag. All desired flags
* are bitwise-ORed together.
* @param pe Receives the position (line and column nubers) of any syntax
* error within the source regular expression string. If this
* information is not wanted, pass NULL for this parameter.
* @param status Receives errors detected by this function.
* @return The URegularExpression object representing the compiled
* pattern.
*
* @stable ICU 3.0
*/
#if !UCONFIG_NO_CONVERSION
U_STABLE URegularExpression * U_EXPORT2
uregex_openC( const char *pattern,
uint32_t flags,
UParseError *pe,
UErrorCode *status);
#endif
/**
* Close the regular expression, recovering all resources (memory) it
* was holding.
*
* @param regexp The regular expression to be closed.
* @stable ICU 3.0
*/
U_STABLE void U_EXPORT2
uregex_close(URegularExpression *regexp);
/**
* Make a copy of a compiled regular expression. Cloning a regular
* expression is faster than opening a second instance from the source
* form of the expression, and requires less memory.
*
* Note that the current input string and the position of any matched text * within it are not cloned; only the pattern itself and and the * match mode flags are copied. *
* Cloning can be particularly useful to threaded applications that perform * multiple match operations in parallel. Each concurrent RE * operation requires its own instance of a URegularExpression. * * @param regexp The compiled regular expression to be cloned. * @param status Receives indication of any errors encountered * @return the cloned copy of the compiled regular expression. * @stable ICU 3.0 */ U_STABLE URegularExpression * U_EXPORT2 uregex_clone(const URegularExpression *regexp, UErrorCode *status); /** * Return a pointer to the source form of the pattern for this regular expression. * * @param regexp The compiled regular expression. * @param patLength This output parameter will be set to the length of the * pattern string. A NULL pointer may be used here if the * pattern length is not needed, as would be the case if * the pattern is known in advance to be a NUL terminated * string. * @param status Receives errors detected by this function. * @return a pointer to the pattern string. The storage for the string is * owned by the regular expression object, and must not be * altered or deleted by the application. The returned string * will remain valid until the regular expression is closed. * @stable ICU 3.0 */ U_STABLE const UChar * U_EXPORT2 uregex_pattern(const URegularExpression *regexp, int32_t *patLength, UErrorCode *status); /** * Get the match mode flags that were specified when compiling this regular expression. * @param status Receives errors detected by this function. * @param regexp The compiled regular expression. * @return The match mode flags * @see URegexpFlag * @stable ICU 3.0 */ U_STABLE int32_t U_EXPORT2 uregex_flags(const URegularExpression *regexp, UErrorCode *status); /** * Set the subject text string upon which the regular expression will look for matches. * This function may be called any number of times, allowing the regular * expression pattern to be applied to different strings. *
* Regular expression matching operations work directly on the application's * string data. No copy is made. The subject string data must not be * altered after calling this function until after all regular expression * operations involving this string data are completed. *
* Zero length strings are permitted. In this case, no subsequent match * operation will dereference the text string pointer. * * @param regexp The compiled regular expression. * @param text The subject text string. * @param textLength The length of the subject text, or -1 if the string * is NUL terminated. * @param status Receives errors detected by this function. * @stable ICU 3.0 */ U_STABLE void U_EXPORT2 uregex_setText(URegularExpression *regexp, const UChar *text, int32_t textLength, UErrorCode *status); /** * Get the subject text that is currently associated with this * regular expression object. This simply returns whatever string * pointer was previously supplied via uregex_setText(). * * @param regexp The compiled regular expression. * @param textLength The length of the string is returned in this output parameter. * A NULL pointer may be used here if the * text length is not needed, as would be the case if * the text is known in advance to be a NUL terminated * string. * @param status Receives errors detected by this function. * @return Poiner to the subject text string currently associated with * this regular expression. * @stable ICU 3.0 */ U_STABLE const UChar * U_EXPORT2 uregex_getText(URegularExpression *regexp, int32_t *textLength, UErrorCode *status); /** * Attempts to match the input string against the pattern. * To succeed, the match must extend to the end of the string, * or cover the complete match region. * * If startIndex >= zero the match operation starts at the specified * index and must extend to the end of the input string. Any region * that has been specified is reset. * * If startIndex == -1 the match must cover the input region, or the entire * input string if no region has been set. This directly corresponds to * Matcher.matches() in Java * * @param regexp The compiled regular expression. * @param startIndex The input string index at which to begin matching, or -1 * to match the input Region. * @param status Receives errors detected by this function. * @return TRUE if there is a match * @stable ICU 3.0 */ U_STABLE UBool U_EXPORT2 uregex_matches(URegularExpression *regexp, int32_t startIndex, UErrorCode *status); /** * Attempts to match the input string, starting from the specified index, against the pattern. * The match may be of any length, and is not required to extend to the end * of the input string. Contrast with uregex_matches(). * *
If startIndex is >= 0 any input region that was set for this * URegularExpression is reset before the operation begins. * *
If the specified starting index == -1 the match begins at the start of the input * region, or at the start of the full string if no region has been specified. * This corresponds directly with Matcher.lookingAt() in Java. * *
If the match succeeds then more information can be obtained via the
* uregexp_start(), uregexp_end(),
* and uregexp_group() functions.
uregex_start(), uregex_end(), and
* uregex_group() will provide more information regarding the match.
*
* @param regexp The compiled regular expression.
* @param startIndex The position in the input string to begin the search, or
* -1 to search within the Input Region.
* @param status A reference to a UErrorCode to receive any errors.
* @return TRUE if a match is found.
* @stable ICU 3.0
*/
U_STABLE UBool U_EXPORT2
uregex_find(URegularExpression *regexp,
int32_t startIndex,
UErrorCode *status);
/**
* Find the next pattern match in the input string. Begin searching
* the input at the location following the end of he previous match,
* or at the start of the string (or region) if there is no
* previous match. If a match is found, uregex_start(), uregex_end(), and
* uregex_group() will provide more information regarding the match.
*
* @param regexp The compiled regular expression.
* @param status A reference to a UErrorCode to receive any errors.
* @return TRUE if a match is found.
* @see uregex_reset
* @stable ICU 3.0
*/
U_STABLE UBool U_EXPORT2
uregex_findNext(URegularExpression *regexp,
UErrorCode *status);
/**
* Get the number of capturing groups in this regular expression's pattern.
* @param regexp The compiled regular expression.
* @param status A reference to a UErrorCode to receive any errors.
* @return the number of capture groups
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_groupCount(URegularExpression *regexp,
UErrorCode *status);
/** Extract the string for the specified matching expression or subexpression.
* Group #0 is the complete string of matched text.
* Group #1 is the text matched by the first set of capturing parentheses.
*
* @param regexp The compiled regular expression.
* @param groupNum The capture group to extract. Group 0 is the complete
* match. The value of this parameter must be
* less than or equal to the number of capture groups in
* the pattern.
* @param dest Buffer to receive the matching string data
* @param destCapacity Capacity of the dest buffer.
* @param status A reference to a UErrorCode to receive any errors.
* @return Length of matching data,
* or -1 if no applicable match.
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_group(URegularExpression *regexp,
int32_t groupNum,
UChar *dest,
int32_t destCapacity,
UErrorCode *status);
/**
* Returns the index in the input string of the start of the text matched by the
* specified capture group during the previous match operation. Return -1 if
* the capture group was not part of the last match.
* Group #0 refers to the complete range of matched text.
* Group #1 refers to the text matched by the first set of capturing parentheses.
*
* @param regexp The compiled regular expression.
* @param groupNum The capture group number
* @param status A reference to a UErrorCode to receive any errors.
* @return the starting position in the input of the text matched
* by the specified group.
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_start(URegularExpression *regexp,
int32_t groupNum,
UErrorCode *status);
/**
* Returns the index in the input string of the position following the end
* of the text matched by the specified capture group.
* Return -1 if the capture group was not part of the last match.
* Group #0 refers to the complete range of matched text.
* Group #1 refers to the text matched by the first set of capturing parentheses.
*
* @param regexp The compiled regular expression.
* @param groupNum The capture group number
* @param status A reference to a UErrorCode to receive any errors.
* @return the index of the position following the last matched character.
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_end(URegularExpression *regexp,
int32_t groupNum,
UErrorCode *status);
/**
* Reset any saved state from the previous match. Has the effect of
* causing uregex_findNext to begin at the specified index, and causing
* uregex_start(), uregex_end() and uregex_group() to return an error
* indicating that there is no match information available. Clears any
* match region that may have been set.
*
* @param regexp The compiled regular expression.
* @param index The position in the text at which a
* uregex_findNext() should begin searching.
* @param status A reference to a UErrorCode to receive any errors.
* @stable ICU 3.0
*/
U_STABLE void U_EXPORT2
uregex_reset(URegularExpression *regexp,
int32_t index,
UErrorCode *status);
/** Sets the limits of the matching region for this URegularExpression.
* The region is the part of the input string that will be considered when matching.
* Invoking this method resets any saved state from the previous match,
* then sets the region to start at the index specified by the start parameter
* and end at the index specified by the end parameter.
*
* Depending on the transparency and anchoring being used (see useTransparentBounds
* and useAnchoringBounds), certain constructs such as anchors may behave differently
* at or around the boundaries of the region
*
* The function will fail if start is greater than limit, or if either index
* is less than zero or greater than the length of the string being matched.
*
* @param regexp The compiled regular expression.
* @param regionStart The index to begin searches at.
* @param regionLimit The index to end searches at (exclusive).
* @param status A pointer to a UErrorCode to receive any errors.
* @stable ICU 4.0
*/
U_DRAFT void U_EXPORT2
uregex_setRegion(URegularExpression *regexp,
int32_t regionStart,
int32_t regionLimit,
UErrorCode *status);
/**
* Reports the start index of the matching region. Any matches found are limited to
* to the region bounded by regionStart (inclusive) and regionEnd (exclusive).
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return The starting index of this matcher's region.
* @stable ICU 4.0
*/
U_DRAFT int32_t U_EXPORT2
uregex_regionStart(const URegularExpression *regexp,
UErrorCode *status);
/**
* Reports the end index (exclusive) of the matching region for this URegularExpression.
* Any matches found are limited to to the region bounded by regionStart (inclusive)
* and regionEnd (exclusive).
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return The ending point of this matcher's region.
* @stable ICU 4.0
*/
U_DRAFT int32_t U_EXPORT2
uregex_regionEnd(const URegularExpression *regexp,
UErrorCode *status);
/**
* Queries the transparency of region bounds for this URegularExpression.
* See useTransparentBounds for a description of transparent and opaque bounds.
* By default, matching boundaries are opaque.
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return TRUE if this matcher is using opaque bounds, false if it is not.
* @stable ICU 4.0
*/
U_DRAFT UBool U_EXPORT2
uregex_hasTransparentBounds(const URegularExpression *regexp,
UErrorCode *status);
/**
* Sets the transparency of region bounds for this URegularExpression.
* Invoking this function with an argument of TRUE will set matches to use transparent bounds.
* If the boolean argument is FALSE, then opaque bounds will be used.
*
* Using transparent bounds, the boundaries of the matching region are transparent
* to lookahead, lookbehind, and boundary matching constructs. Those constructs can
* see text beyond the boundaries of the region while checking for a match.
*
* With opaque bounds, no text outside of the matching region is visible to lookahead,
* lookbehind, and boundary matching constructs.
*
* By default, opaque bounds are used.
*
* @param regexp The compiled regular expression.
* @param b TRUE for transparent bounds; FALSE for opaque bounds
* @param status A pointer to a UErrorCode to receive any errors.
* @stable ICU 4.0
**/
U_DRAFT void U_EXPORT2
uregex_useTransparentBounds(URegularExpression *regexp,
UBool b,
UErrorCode *status);
/**
* Return true if this URegularExpression is using anchoring bounds.
* By default, anchoring region bounds are used.
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return TRUE if this matcher is using anchoring bounds.
* @stable ICU 4.0
*/
U_DRAFT UBool U_EXPORT2
uregex_hasAnchoringBounds(const URegularExpression *regexp,
UErrorCode *status);
/**
* Set whether this URegularExpression is using Anchoring Bounds for its region.
* With anchoring bounds, pattern anchors such as ^ and $ will match at the start
* and end of the region. Without Anchoring Bounds, anchors will only match at
* the positions they would in the complete text.
*
* Anchoring Bounds are the default for regions.
*
* @param regexp The compiled regular expression.
* @param b TRUE if to enable anchoring bounds; FALSE to disable them.
* @param status A pointer to a UErrorCode to receive any errors.
* @stable ICU 4.0
*/
U_DRAFT void U_EXPORT2
uregex_useAnchoringBounds(URegularExpression *regexp,
UBool b,
UErrorCode *status);
/**
* Return TRUE if the most recent matching operation touched the
* end of the text being processed. In this case, additional input text could
* change the results of that match.
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return TRUE if the most recent match hit the end of input
* @stable ICU 4.0
*/
U_DRAFT UBool U_EXPORT2
uregex_hitEnd(const URegularExpression *regexp,
UErrorCode *status);
/**
* Return TRUE the most recent match succeeded and additional input could cause
* it to fail. If this function returns false and a match was found, then more input
* might change the match but the match won't be lost. If a match was not found,
* then requireEnd has no meaning.
*
* @param regexp The compiled regular expression.
* @param status A pointer to a UErrorCode to receive any errors.
* @return TRUE if more input could cause the most recent match to no longer match.
* @stable ICU 4.0
*/
U_DRAFT UBool U_EXPORT2
uregex_requireEnd(const URegularExpression *regexp,
UErrorCode *status);
/**
* Replaces every substring of the input that matches the pattern
* with the given replacement string. This is a convenience function that
* provides a complete find-and-replace-all operation.
*
* This method scans the input string looking for matches of the pattern.
* Input that is not part of any match is copied unchanged to the
* destination buffer. Matched regions are replaced in the output
* buffer by the replacement string. The replacement string may contain
* references to capture groups; these take the form of $1, $2, etc.
*
* @param regexp The compiled regular expression.
* @param replacementText A string containing the replacement text.
* @param replacementLength The length of the replacement string, or
* -1 if it is NUL terminated.
* @param destBuf A (UChar *) buffer that will receive the result.
* @param destCapacity The capacity of the desitnation buffer.
* @param status A reference to a UErrorCode to receive any errors.
* @return The length of the string resulting from the find
* and replace operation. In the event that the
* destination capacity is inadequate, the return value
* is still the full length of the untruncated string.
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_replaceAll(URegularExpression *regexp,
const UChar *replacementText,
int32_t replacementLength,
UChar *destBuf,
int32_t destCapacity,
UErrorCode *status);
/**
* Replaces the first substring of the input that matches the pattern
* with the given replacement string. This is a convenience function that
* provides a complete find-and-replace operation.
*
* This method scans the input string looking for a match of the pattern.
* All input that is not part of the match is copied unchanged to the
* destination buffer. The matched region is replaced in the output
* buffer by the replacement string. The replacement string may contain
* references to capture groups; these take the form of $1, $2, etc.
*
* @param regexp The compiled regular expression.
* @param replacementText A string containing the replacement text.
* @param replacementLength The length of the replacement string, or
* -1 if it is NUL terminated.
* @param destBuf A (UChar *) buffer that will receive the result.
* @param destCapacity The capacity of the desitnation buffer.
* @param status a reference to a UErrorCode to receive any errors.
* @return The length of the string resulting from the find
* and replace operation. In the event that the
* destination capacity is inadequate, the return value
* is still the full length of the untruncated string.
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_replaceFirst(URegularExpression *regexp,
const UChar *replacementText,
int32_t replacementLength,
UChar *destBuf,
int32_t destCapacity,
UErrorCode *status);
/**
* Implements a replace operation intended to be used as part of an
* incremental find-and-replace.
*
* The input string, starting from the end of the previous match and ending at * the start of the current match, is appended to the destination string. Then the * replacement string is appended to the output string, * including handling any substitutions of captured text.
* *A note on preflight computation of buffersize and error handling: * Calls to uregex_appendReplacement() and uregex_appendTail() are * designed to be chained, one after another, with the destination * buffer pointer and buffer capacity updated after each in preparation * to for the next. If the destination buffer is exhausted partway through such a * sequence, a U_BUFFER_OVERFLOW_ERROR status will be returned. Normal * ICU conventions are for a function to perform no action if it is * called with an error status, but for this one case, uregex_appendRepacement() * will operate normally so that buffer size computations will complete * correctly. * *
For simple, prepackaged, non-incremental find-and-replace * operations, see replaceFirst() or replaceAll().
* * @param regexp The regular expression object. * @param replacementText The string that will replace the matched portion of the * input string as it is copied to the destination buffer. * The replacement text may contain references ($1, for * example) to capture groups from the match. * @param replacementLength The length of the replacement text string, * or -1 if the string is NUL terminated. * @param destBuf The buffer into which the results of the * find-and-replace are placed. On return, this pointer * will be updated to refer to the beginning of the * unused portion of buffer, leaving it in position for * a subsequent call to this function. * @param destCapacity The size of the output buffer, On return, this * parameter will be updated to reflect the space remaining * unused in the output buffer. * @param status A reference to a UErrorCode to receive any errors. * @return The length of the result string. In the event that * destCapacity is inadequate, the full length of the * untruncated output string is returned. * * @stable ICU 3.0 * */ U_STABLE int32_t U_EXPORT2 uregex_appendReplacement(URegularExpression *regexp, const UChar *replacementText, int32_t replacementLength, UChar **destBuf, int32_t *destCapacity, UErrorCode *status); /** * As the final step in a find-and-replace operation, append the remainder * of the input string, starting at the position following the last match, * to the destination string.uregex_appendTail() is intended
* to be invoked after one or more invocations of the
* uregex_appendReplacement() function.
*
* @param regexp The regular expression object. This is needed to
* obtain the input string and with the position
* of the last match within it.
* @param destBuf The buffer in which the results of the
* find-and-replace are placed. On return, the pointer
* will be updated to refer to the beginning of the
* unused portion of buffer.
* @param destCapacity The size of the output buffer, On return, this
* value will be updated to reflect the space remaining
* unused in the output buffer.
* @param status A reference to a UErrorCode to receive any errors.
* @return The length of the result string. In the event that
* destCapacity is inadequate, the full length of the
* untruncated output string is returned.
*
* @stable ICU 3.0
*/
U_STABLE int32_t U_EXPORT2
uregex_appendTail(URegularExpression *regexp,
UChar **destBuf,
int32_t *destCapacity,
UErrorCode *status);
/**
* Split a string into fields. Somewhat like split() from Perl.
* The pattern matches identify delimiters that separate the input
* into fields. The input data between the matches becomes the
* fields themselves.
* * Each of the fields is copied from the input string to the destination * buffer, and the NUL terminated. The position of each field within * the destination buffer is returned in the destFields array. * * Note: another choice for the design of this function would be to not * copy the resulting fields at all, but to return indexes and * lengths within the source text. * Advantages would be * o Faster. No Copying. * o Nothing extra needed when field data may contain embedded NUL chars. * o Less memory needed if working on large data. * Disadvantages * o Less consistent with C++ split, which copies into an * array of UnicodeStrings. * o No NUL termination, extracted fields would be less convenient * to use in most cases. * o Possible problems in the future, when support Unicode Normalization * could cause the fields to not correspond exactly to * a range of the source text. * * @param regexp The compiled regular expression. * @param destBuf A (UChar *) buffer to receive the fields that * are extracted from the input string. These * field pointers will refer to positions within the * destination buffer supplied by the caller. Any * extra positions within the destFields array will be * set to NULL. * @param destCapacity The capacity of the destBuf. * @param requiredCapacity The actual capacity required of the destBuf. * If destCapacity is too small, requiredCapacity will return * the total capacity required to hold all of the output, and * a U_BUFFER_OVERFLOW_ERROR will be returned. * @param destFields An array to be filled with the position of each * of the extracted fields within destBuf. * @param destFieldsCapacity The number of elements in the destFields array. * If the number of fields found is less than destFieldsCapacity, * the extra destFields elements are set to zero. * If destFieldsCapacity is too small, the trailing part of the * input, including any field delimiters, is treated as if it * were the last field - it is copied to the destBuf, and * its position is in the destBuf is stored in the last element * of destFields. This behavior mimics that of Perl. It is not * an error condition, and no error status is returned when all destField * positions are used. * @param status A reference to a UErrorCode to receive any errors. * @return The number of fields into which the input string was split. * @stable ICU 3.0 */ U_STABLE int32_t U_EXPORT2 uregex_split( URegularExpression *regexp, UChar *destBuf, int32_t destCapacity, int32_t *requiredCapacity, UChar *destFields[], int32_t destFieldsCapacity, UErrorCode *status); /** * Set a processing time limit for match operations with this URegularExpression. * * Some patterns, when matching certain strings, can run in exponential time. * For practical purposes, the match operation may appear to be in an * infinite loop. * When a limit is set a match operation will fail with an error if the * limit is exceeded. *
* The units of the limit are steps of the match engine. * Correspondence with actual processor time will depend on the speed * of the processor and the details of the specific pattern, but will * typically be on the order of milliseconds. *
* By default, the matching time is not limited. *
* * @param regexp The compiled regular expression. * @param limit The limit value, or 0 for no limit. * @param status A reference to a UErrorCode to receive any errors. * @stable ICU 4.0 */ U_DRAFT void U_EXPORT2 uregex_setTimeLimit(URegularExpression *regexp, int32_t limit, UErrorCode *status); /** * Get the time limit for for matches with this URegularExpression. * A return value of zero indicates that there is no limit. * * @param regexp The compiled regular expression. * @param status A reference to a UErrorCode to receive any errors. * @return the maximum allowed time for a match, in units of processing steps. * @stable ICU 4.0 */ U_DRAFT int32_t U_EXPORT2 uregex_getTimeLimit(const URegularExpression *regexp, UErrorCode *status); /** * Set the amount of heap storage avaliable for use by the match backtracking stack. *
* ICU uses a backtracking regular expression engine, with the backtrack stack * maintained on the heap. This function sets the limit to the amount of memory * that can be used for this purpose. A backtracking stack overflow will * result in an error from the match operation that caused it. *
* A limit is desirable because a malicious or poorly designed pattern can use * excessive memory, potentially crashing the process. A limit is enabled * by default. *
* @param regexp The compiled regular expression. * @param limit The maximum size, in bytes, of the matching backtrack stack. * A value of -1 means no limit. * The limit must be greater than zero, or -1. * @param status A reference to a UErrorCode to receive any errors. * * @stable ICU 4.0 */ U_DRAFT void U_EXPORT2 uregex_setStackLimit(URegularExpression *regexp, int32_t limit, UErrorCode *status); /** * Get the size of the heap storage available for use by the back tracking stack. * * @return the maximum backtracking stack size, in bytes, or zero if the * stack size is unlimited. * @stable ICU 4.0 */ U_DRAFT int32_t U_EXPORT2 uregex_getStackLimit(const URegularExpression *regexp, UErrorCode *status); /** * Function pointer for a regular expression matching callback function. * When set, a callback function will be called periodically during matching * operations. If the call back function returns FALSE, the matching * operation will be terminated early. * * Note: the callback function must not call other functions on this * URegularExpression. * * @param context context pointer. The callback function will be invoked * with the context specified at the time that * uregex_setMatchCallback() is called. * @param steps the accumulated processing time, in match steps, * for this matching operation. * @return TRUE to continue the matching operation. * FALSE to terminate the matching operation. * @stable ICU 4.0 */ U_CDECL_BEGIN typedef UBool U_CALLCONV URegexMatchCallback ( const void *context, int32_t steps); U_CDECL_END /** * Set a callback function for this URegularExpression. * During matching operations the function will be called periodically, * giving the application the opportunity to terminate a long-running * match. * * @param regexp The compiled regular expression. * @param callback A pointer to the user-supplied callback function. * @param context User context pointer. The value supplied at the * time the callback function is set will be saved * and passed to the callback each time that it is called. * @param status A reference to a UErrorCode to receive any errors. * @stable ICU 4.0 */ U_DRAFT void U_EXPORT2 uregex_setMatchCallback(URegularExpression *regexp, URegexMatchCallback *callback, const void *context, UErrorCode *status); /** * Get the callback function for this URegularExpression. * * @param regexp The compiled regular expression. * @param callback Out paramater, receives a pointer to the user-supplied * callback function. * @param context Out parameter, receives the user context pointer that * was set when uregex_setMatchCallback() was called. * @param status A reference to a UErrorCode to receive any errors. * @stable ICU 4.0 */ U_DRAFT void U_EXPORT2 uregex_getMatchCallback(const URegularExpression *regexp, URegexMatchCallback **callback, const void **context, UErrorCode *status); #endif /* !UCONFIG_NO_REGULAR_EXPRESSIONS */ #endif /* UREGEX_H */