633 lines
27 KiB
C
633 lines
27 KiB
C
/*
|
||
**********************************************************************
|
||
* Copyright (C) 2001 IBM and others. All rights reserved.
|
||
**********************************************************************
|
||
* Date Name Description
|
||
* 06/28/2001 synwee Creation.
|
||
**********************************************************************
|
||
*/
|
||
#ifndef USEARCH_H
|
||
#define USEARCH_H
|
||
|
||
#include "unicode/utypes.h"
|
||
|
||
#if !UCONFIG_NO_COLLATION
|
||
|
||
#include "unicode/ucol.h"
|
||
#include "unicode/ucoleitr.h"
|
||
#include "unicode/ubrk.h"
|
||
|
||
/**
|
||
* \file
|
||
* \brief C API: StringSearch
|
||
*
|
||
* C Apis for an engine that provides language-sensitive text searching based
|
||
* on the comparison rules defined in a <tt>UCollator</tt> data struct,
|
||
* see <tt>ucol.h</tt>. This ensures that language eccentricity can be
|
||
* handled, e.g. for the German collator, characters ß and SS will be matched
|
||
* if case is chosen to be ignored.
|
||
* See the <a href=http://oss.software.ibm.com/icu/develop/collation/ICU_collation_design.htm>
|
||
* "ICU Collation Design Document"</a> for more information.
|
||
* <p>
|
||
* The algorithm implemented is a modified form of the Boyer Moore's search.
|
||
* For more information see
|
||
* <a href=http://oss.software.ibm.com/icu/docs/papers/text-search.html>
|
||
* "Efficient Text Searching in Java"</a>, published in <i>Java Report</i>
|
||
* in February, 1999, for further information on the algorithm.
|
||
* <p>
|
||
* There are 2 match options for selection:<br>
|
||
* Let S' be the sub-string of a text string S between the offsets start and
|
||
* end <start, end>.
|
||
* <br>
|
||
* A pattern string P matches a text string S at the offsets <start, end>
|
||
* if
|
||
* <pre>
|
||
* option 1. Some canonical equivalent of P matches some canonical equivalent
|
||
* of S'
|
||
* option 2. P matches S' and if P starts or ends with a combining mark,
|
||
* there exists no non-ignorable combining mark before or after S’
|
||
* in S respectively.
|
||
* </pre>
|
||
* Option 2. will be the default·
|
||
* <p>
|
||
* This search has APIs similar to that of other text iteration mechanisms
|
||
* such as the break iterators in <tt>ubrk.h</tt>. Using these
|
||
* APIs, it is easy to scan through text looking for all occurances of
|
||
* a given pattern. This search iterator allows changing of direction by
|
||
* calling a <tt>reset</tt> followed by a <tt>next</tt> or <tt>previous</tt>.
|
||
* Though a direction change can occur without calling <tt>reset</tt> first,
|
||
* this operation comes with some speed penalty.
|
||
* Generally, match results in the forward direction will match the result
|
||
* matches in the backwards direction in the reverse order
|
||
* <p>
|
||
* <tt>usearch.h</tt> provides APIs to specify the starting position
|
||
* within the text string to be searched, e.g. <tt>usearch_setOffset</tt>,
|
||
* <tt>usearch_preceding</tt> and <tt>usearch_following</tt>. Since the
|
||
* starting position will be set as it is specified, please take note that
|
||
* there are some dangerous positions which the search may render incorrect
|
||
* results:
|
||
* <ul>
|
||
* <li> The midst of a substring that requires normalization.
|
||
* <li> If the following match is to be found, the position should not be the
|
||
* second character which requires to be swapped with the preceding
|
||
* character. Vice versa, if the preceding match is to be found,
|
||
* position to search from should not be the first character which
|
||
* requires to be swapped with the next character. E.g certain Thai and
|
||
* Lao characters require swapping.
|
||
* <li> If a following pattern match is to be found, any position within a
|
||
* contracting sequence except the first will fail. Vice versa if a
|
||
* preceding pattern match is to be found, a invalid starting point
|
||
* would be any character within a contracting sequence except the last.
|
||
* </ul>
|
||
* <p>
|
||
* A breakiterator can be used if only matches at logical breaks are desired.
|
||
* Using a breakiterator will only give you results that exactly matches the
|
||
* boundaries given by the breakiterator. For instance the pattern "e" will
|
||
* not be found in the string "\u00e9" if a character break iterator is used.
|
||
* <p>
|
||
* Options are provided to handle overlapping matches.
|
||
* E.g. In English, overlapping matches produces the result 0 and 2
|
||
* for the pattern "abab" in the text "ababab", where else mutually
|
||
* exclusive matches only produce the result of 0.
|
||
* <p>
|
||
* Though collator attributes will be taken into consideration while
|
||
* performing matches, there are no APIs here for setting and getting the
|
||
* attributes. These attributes can be set by getting the collator
|
||
* from <tt>usearch_getCollator</tt> and using the APIs in <tt>ucol.h</tt>.
|
||
* Lastly to update String Search to the new collator attributes,
|
||
* usearch_reset() has to be called.
|
||
* <p>
|
||
* Restriction: <br>
|
||
* Currently there are no composite characters that consists of a
|
||
* character with combining class > 0 before a character with combining
|
||
* class == 0. However, if such a character exists in the future, the
|
||
* search mechanism does not guarantee the results for option 1.
|
||
*
|
||
* <p>
|
||
* Example of use:<br>
|
||
* <pre><code>
|
||
* char *tgtstr = "The quick brown fox jumped over the lazy fox";
|
||
* char *patstr = "fox";
|
||
* UChar target[64];
|
||
* UChar pattern[16];
|
||
* UErrorCode status = U_ZERO_ERROR;
|
||
* u_uastrcpy(target, tgtstr);
|
||
* u_uastrcpy(pattern, patstr);
|
||
*
|
||
* UStringSearch *search = usearch_open(pattern, -1, target, -1, "en_US",
|
||
* &status);
|
||
* if (U_SUCCESS(status)) {
|
||
* for (int pos = usearch_first(search, &status);
|
||
* pos != USEARCH_DONE;
|
||
* pos = usearch_next(search, &status)) {
|
||
* printf("Found match at %d pos, length is %d\n", pos,
|
||
* usearch_getMatchLength(search));
|
||
* }
|
||
* }
|
||
* </code></pre>
|
||
* @since ICU 2.0
|
||
*/
|
||
|
||
/**
|
||
* DONE is returned by previous() and next() after all valid matches have
|
||
* been returned, and by first() and last() if there are no matches at all.
|
||
*/
|
||
#define USEARCH_DONE -1
|
||
|
||
/**
|
||
* Data structure for searching
|
||
*/
|
||
struct UStringSearch;
|
||
/**
|
||
* Data structure for searching
|
||
*/
|
||
typedef struct UStringSearch UStringSearch;
|
||
|
||
typedef enum {
|
||
/** Option for overlapping matches */
|
||
USEARCH_OVERLAP,
|
||
/**
|
||
Option for canonical matches. option 1 in header documentation.
|
||
The default value will be USEARCH_OFF
|
||
*/
|
||
USEARCH_CANONICAL_MATCH,
|
||
USEARCH_ATTRIBUTE_COUNT
|
||
} USearchAttribute;
|
||
|
||
typedef enum {
|
||
/** default value for any USearchAttribute */
|
||
USEARCH_DEFAULT = -1,
|
||
/** value for USEARCH_OVERLAP and USEARCH_CANONICAL_MATCH */
|
||
USEARCH_OFF,
|
||
/** value for USEARCH_OVERLAP and USEARCH_CANONICAL_MATCH */
|
||
USEARCH_ON,
|
||
USEARCH_ATTRIBUTE_VALUE_COUNT
|
||
} USearchAttributeValue;
|
||
|
||
/* open and close ------------------------------------------------------ */
|
||
|
||
/**
|
||
* Creating a search iterator data struct using the argument locale language
|
||
* rule set. A collator will be created in the process, which will be owned by
|
||
* this search and will be deleted in <tt>usearch_close</tt>.
|
||
* @param pattern for matching
|
||
* @param patternlength length of the pattern, -1 for null-termination
|
||
* @param text text string
|
||
* @param textlength length of the text string, -1 for null-termination
|
||
* @param locale name of locale for the rules to be used
|
||
* @param breakiter A BreakIterator that will be used to restrict the points
|
||
* at which matches are detected. If a match is found, but
|
||
* the match's start or end index is not a boundary as
|
||
* determined by the <tt>BreakIterator</tt>, the match will
|
||
* be rejected and another will be searched for.
|
||
* If this parameter is <tt>NULL</tt>, no break detection is
|
||
* attempted.
|
||
* @param status for errors if it occurs. If pattern or text is NULL, or if
|
||
* patternlength or textlength is 0 then an
|
||
* U_ILLEGAL_ARGUMENT_ERROR is returned.
|
||
* @return search iterator data structure, or NULL if there is an error.
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI UStringSearch * U_EXPORT2 usearch_open(const UChar *pattern,
|
||
int32_t patternlength,
|
||
const UChar *text,
|
||
int32_t textlength,
|
||
const char *locale,
|
||
UBreakIterator *breakiter,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Creating a search iterator data struct using the argument collator language
|
||
* rule set. Note, user retains the ownership of this collator, thus the
|
||
* responsibility of deletion lies with the user.
|
||
* @param pattern for matching
|
||
* @param patternlength length of the pattern, -1 for null-termination
|
||
* @param text text string
|
||
* @param textlength length of the text string, -1 for null-termination
|
||
* @param collator used for the language rules
|
||
* @param breakiter A BreakIterator that will be used to restrict the points
|
||
* at which matches are detected. If a match is found, but
|
||
* the match's start or end index is not a boundary as
|
||
* determined by the <tt>BreakIterator</tt>, the match will
|
||
* be rejected and another will be searched for.
|
||
* If this parameter is <tt>NULL</tt>, no break detection is
|
||
* attempted.
|
||
* @param status for errors if it occurs. If collator, pattern or text is NULL,
|
||
* or if patternlength or textlength is 0 then an
|
||
* U_ILLEGAL_ARGUMENT_ERROR is returned.
|
||
* @return search iterator data structure, or NULL if there is an error.
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI UStringSearch * U_EXPORT2 usearch_openFromCollator(
|
||
const UChar *pattern,
|
||
int32_t patternlength,
|
||
const UChar *text,
|
||
int32_t textlength,
|
||
const UCollator *collator,
|
||
UBreakIterator *breakiter,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Destroying and cleaning up the search iterator data struct.
|
||
* If a collator is created in <tt>usearch_open</tt>, it will be destroyed here.
|
||
* @param searchiter data struct to clean up
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_close(UStringSearch *strsrch);
|
||
|
||
/* get and set methods -------------------------------------------------- */
|
||
|
||
/**
|
||
* Sets the current position in the text string which the next search will
|
||
* start from. Clears previous states.
|
||
* This method takes the argument index and sets the position in the text
|
||
* string accordingly without checking if the index is pointing to a
|
||
* valid starting point to begin searching.
|
||
* Search positions that may render incorrect results are highlighted in the
|
||
* header comments
|
||
* @param strsrch search iterator data struct
|
||
* @param position position to start next search from. If position is less
|
||
* than or greater than the text range for searching,
|
||
* an U_INDEX_OUTOFBOUNDS_ERROR will be returned
|
||
* @param status error status if any.
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setOffset(UStringSearch *strsrch,
|
||
int32_t position,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Return the current index in the string text being searched.
|
||
* If the iteration has gone past the end of the text (or past the beginning
|
||
* for a backwards search), <tt>USEARCH_DONE</tt> is returned.
|
||
* @param strsrch search iterator data struct
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_getOffset(const UStringSearch *strsrch);
|
||
|
||
/**
|
||
* Sets the text searching attributes located in the enum USearchAttribute
|
||
* with values from the enum USearchAttributeValue.
|
||
* <tt>USEARCH_DEFAULT</tt> can be used for all attributes for resetting.
|
||
* @param strsrch search iterator data struct
|
||
* @param attribute text attribute to be set
|
||
* @param value text attribute value
|
||
* @param status for errors if it occurs
|
||
* @see #usearch_getAttribute
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setAttribute(UStringSearch *strsrch,
|
||
USearchAttribute attribute,
|
||
USearchAttributeValue value,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Gets the text searching attributes.
|
||
* @param strsrch search iterator data struct
|
||
* @param attribute text attribute to be retrieve
|
||
* @return text attribute value
|
||
* @see #usearch_setAttribute
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI USearchAttributeValue U_EXPORT2 usearch_getAttribute(
|
||
const UStringSearch *strsrch,
|
||
USearchAttribute attribute);
|
||
|
||
/**
|
||
* Returns the index to the match in the text string that was searched.
|
||
* This call returns a valid result only after a successful call to
|
||
* <tt>usearch_first</tt>, <tt>usearch_next</tt>, <tt>usearch_previous</tt>,
|
||
* or <tt>usearch_last</tt>.
|
||
* Just after construction, or after a searching method returns
|
||
* <tt>USEARCH_DONE</tt>, this method will return <tt>USEARCH_DONE</tt>.
|
||
* <p>
|
||
* Use <tt>usearch_getMatchedLength</tt> to get the matched string length.
|
||
* @param strsrch search iterator data struct
|
||
* @return index to a substring within the text string that is being
|
||
* searched.
|
||
* @see #usearch_first
|
||
* @see #usearch_next
|
||
* @see #usearch_previous
|
||
* @see #usearch_last
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_getMatchedStart(
|
||
const UStringSearch *strsrch);
|
||
|
||
/**
|
||
* Returns the length of text in the string which matches the search pattern.
|
||
* This call returns a valid result only after a successful call to
|
||
* <tt>usearch_first</tt>, <tt>usearch_next</tt>, <tt>usearch_previous</tt>,
|
||
* or <tt>usearch_last</tt>.
|
||
* Just after construction, or after a searching method returns
|
||
* <tt>USEARCH_DONE</tt>, this method will return 0.
|
||
* @param strsrch search iterator data struct
|
||
* @return The length of the match in the string text, or 0 if there is no
|
||
* match currently.
|
||
* @see #usearch_first
|
||
* @see #usearch_next
|
||
* @see #usearch_previous
|
||
* @see #usearch_last
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_getMatchedLength(
|
||
const UStringSearch *strsrch);
|
||
|
||
/**
|
||
* Returns the text that was matched by the most recent call to
|
||
* <tt>usearch_first</tt>, <tt>usearch_next</tt>, <tt>usearch_previous</tt>,
|
||
* or <tt>usearch_last</tt>.
|
||
* If the iterator is not pointing at a valid match (e.g. just after
|
||
* construction or after <tt>USEARCH_DONE</tt> has been returned, returns
|
||
* an empty string. If result is not large enough to store the matched text,
|
||
* result will be filled with the partial text and an U_BUFFER_OVERFLOW_ERROR
|
||
* will be returned in status. result will be null-terminated whenever
|
||
* possible. If the buffer fits the matched text exactly, a null-termination
|
||
* is not possible, then a U_STRING_NOT_TERMINATED_ERROR set in status.
|
||
* Pre-flighting can be either done with length = 0 or the API
|
||
* <tt>usearch_getMatchLength</tt>.
|
||
* @param strsrch search iterator data struct
|
||
* @param result UChar buffer to store the matched string
|
||
* @param resultCapacity length of the result buffer
|
||
* @param status error returned if result is not large enough
|
||
* @return exact length of the matched text, not counting the null-termination
|
||
* @see #usearch_first
|
||
* @see #usearch_next
|
||
* @see #usearch_previous
|
||
* @see #usearch_last
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_getMatchedText(const UStringSearch *strsrch,
|
||
UChar *result,
|
||
int32_t resultCapacity,
|
||
UErrorCode *status);
|
||
|
||
#if !UCONFIG_NO_BREAK_ITERATION
|
||
|
||
/**
|
||
* Set the BreakIterator that will be used to restrict the points at which
|
||
* matches are detected.
|
||
* @param strsrch search iterator data struct
|
||
* @param breakiter A BreakIterator that will be used to restrict the points
|
||
* at which matches are detected. If a match is found, but
|
||
* the match's start or end index is not a boundary as
|
||
* determined by the <tt>BreakIterator</tt>, the match will
|
||
* be rejected and another will be searched for.
|
||
* If this parameter is <tt>NULL</tt>, no break detection is
|
||
* attempted.
|
||
* @param status for errors if it occurs
|
||
* @see #usearch_getBreakIterator
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setBreakIterator(UStringSearch *strsrch,
|
||
UBreakIterator *breakiter,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the BreakIterator that is used to restrict the points at which
|
||
* matches are detected. This will be the same object that was passed to the
|
||
* constructor or to <tt>usearch_setBreakIterator</tt>. Note that
|
||
* <tt>NULL</tt>
|
||
* is a legal value; it means that break detection should not be attempted.
|
||
* @param strsrch search iterator data struct
|
||
* @return break iterator used
|
||
* @see #usearch_setBreakIterator
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI const UBreakIterator * U_EXPORT2 usearch_getBreakIterator(
|
||
const UStringSearch *strsrch);
|
||
|
||
#endif
|
||
|
||
/**
|
||
* Set the string text to be searched. Text iteration will hence begin at the
|
||
* start of the text string. This method is useful if you want to re-use an
|
||
* iterator to search for the same pattern within a different body of text.
|
||
* @param strsrch search iterator data struct
|
||
* @param text new string to look for match
|
||
* @param textlength length of the new string, -1 for null-termination
|
||
* @param status for errors if it occurs. If text is NULL, or textlength is 0
|
||
* then an U_ILLEGAL_ARGUMENT_ERROR is returned with no change
|
||
* done to strsrch.
|
||
* @see #usearch_getText
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setText( UStringSearch *strsrch,
|
||
const UChar *text,
|
||
int32_t textlength,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Return the string text to be searched.
|
||
* @param strsrch search iterator data struct
|
||
* @param length returned string text length
|
||
* @return string text
|
||
* @see #usearch_setText
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI const UChar * U_EXPORT2 usearch_getText(const UStringSearch *strsrch,
|
||
int32_t *length);
|
||
|
||
/**
|
||
* Gets the collator used for the language rules.
|
||
* <p>
|
||
* Deleting the returned <tt>UCollator</tt> before calling
|
||
* <tt>usearch_close</tt> would cause the string search to fail.
|
||
* <tt>usearch_close</tt> will delete the collator if this search owns it.
|
||
* @param strsrch search iterator data struct
|
||
* @return collator
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI UCollator * U_EXPORT2 usearch_getCollator(
|
||
const UStringSearch *strsrch);
|
||
|
||
/**
|
||
* Sets the collator used for the language rules. User retains the ownership
|
||
* of this collator, thus the responsibility of deletion lies with the user.
|
||
* This method causes internal data such as Boyer-Moore shift tables to
|
||
* be recalculated, but the iterator's position is unchanged.
|
||
* @param strsrch search iterator data struct
|
||
* @param collator to be used
|
||
* @param status for errors if it occurs
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setCollator( UStringSearch *strsrch,
|
||
const UCollator *collator,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Sets the pattern used for matching.
|
||
* Internal data like the Boyer Moore table will be recalculated, but the
|
||
* iterator's position is unchanged.
|
||
* @param strsrch search iterator data struct
|
||
* @param pattern string
|
||
* @param patternlength pattern length, -1 for null-terminated string
|
||
* @param status for errors if it occurs. If text is NULL, or textlength is 0
|
||
* then an U_ILLEGAL_ARGUMENT_ERROR is returned with no change
|
||
* done to strsrch.
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_setPattern( UStringSearch *strsrch,
|
||
const UChar *pattern,
|
||
int32_t patternlength,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Gets the search pattern
|
||
* @param strsrch search iterator data struct
|
||
* @param length return length of the pattern, -1 indicates that the pattern
|
||
* is null-terminated
|
||
* @return pattern string
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI const UChar * U_EXPORT2 usearch_getPattern(
|
||
const UStringSearch *strsrch,
|
||
int32_t *length);
|
||
|
||
/* methods ------------------------------------------------------------- */
|
||
|
||
/**
|
||
* Returns the first index at which the string text matches the search
|
||
* pattern.
|
||
* The iterator is adjusted so that its current index (as returned by
|
||
* <tt>usearch_getOffset</tt>) is the match position if one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>.
|
||
* @param strsrch search iterator data struct
|
||
* @param status for errors if it occurs
|
||
* @return The character index of the first match, or
|
||
* <tt>USEARCH_DONE</tt> if there are no matches.
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_first(UStringSearch *strsrch,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the first index greater than <tt>position</tt> at which the string
|
||
* text
|
||
* matches the search pattern. The iterator is adjusted so that its current
|
||
* index (as returned by <tt>usearch_getOffset</tt>) is the match position if
|
||
* one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>
|
||
* <p>
|
||
* Search positions that may render incorrect results are highlighted in the
|
||
* header comments. If position is less than or greater than the text range
|
||
* for searching, an U_INDEX_OUTOFBOUNDS_ERROR will be returned
|
||
* @param strsrch search iterator data struct
|
||
* @param position to start the search at
|
||
* @param status for errors if it occurs
|
||
* @return The character index of the first match following <tt>pos</tt>,
|
||
* or <tt>USEARCH_DONE</tt> if there are no matches.
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_following(UStringSearch *strsrch,
|
||
int32_t position,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the last index in the target text at which it matches the search
|
||
* pattern. The iterator is adjusted so that its current
|
||
* index (as returned by <tt>usearch_getOffset</tt>) is the match position if
|
||
* one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>.
|
||
* @param strsrch search iterator data struct
|
||
* @param status for errors if it occurs
|
||
* @return The index of the first match, or <tt>USEARCH_DONE</tt> if there
|
||
* are no matches.
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_last(UStringSearch *strsrch,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the first index less than <tt>position</tt> at which the string text
|
||
* matches the search pattern. The iterator is adjusted so that its current
|
||
* index (as returned by <tt>usearch_getOffset</tt>) is the match position if
|
||
* one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>
|
||
* <p>
|
||
* Search positions that may render incorrect results are highlighted in the
|
||
* header comments. If position is less than or greater than the text range
|
||
* for searching, an U_INDEX_OUTOFBOUNDS_ERROR will be returned
|
||
* @param strsrch search iterator data struct
|
||
* @param position index position the search is to begin at
|
||
* @param status for errors if it occurs
|
||
* @return The character index of the first match preceding <tt>pos</tt>,
|
||
* or <tt>USEARCH_DONE</tt> if there are no matches.
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_preceding(UStringSearch *strsrch,
|
||
int32_t position,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the index of the next point at which the string text matches the
|
||
* search pattern, starting from the current position.
|
||
* The iterator is adjusted so that its current
|
||
* index (as returned by <tt>usearch_getOffset</tt>) is the match position if
|
||
* one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>
|
||
* @param strsrch search iterator data struct
|
||
* @param status for errors if it occurs
|
||
* @return The index of the next match after the current position, or
|
||
* <tt>USEARCH_DONE</tt> if there are no more matches.
|
||
* @see #usearch_first
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_next(UStringSearch *strsrch,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Returns the index of the previous point at which the string text matches
|
||
* the search pattern, starting at the current position.
|
||
* The iterator is adjusted so that its current
|
||
* index (as returned by <tt>usearch_getOffset</tt>) is the match position if
|
||
* one was found.
|
||
* If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
|
||
* the iterator will be adjusted to the index <tt>USEARCH_DONE</tt>
|
||
* @param strsrch search iterator data struct
|
||
* @param status for errors if it occurs
|
||
* @return The index of the previous match before the current position,
|
||
* or <tt>USEARCH_DONE</tt> if there are no more matches.
|
||
* @see #usearch_last
|
||
* @see #usearch_getOffset
|
||
* @see #USEARCH_DONE
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI int32_t U_EXPORT2 usearch_previous(UStringSearch *strsrch,
|
||
UErrorCode *status);
|
||
|
||
/**
|
||
* Reset the iteration.
|
||
* Search will begin at the start of the text string if a forward iteration
|
||
* is initiated before a backwards iteration. Otherwise if a backwards
|
||
* iteration is initiated before a forwards iteration, the search will begin
|
||
* at the end of the text string.
|
||
* @param strsrch search iterator data struct
|
||
* @see #usearch_first
|
||
* @draft ICU 2.0
|
||
*/
|
||
U_CAPI void U_EXPORT2 usearch_reset(UStringSearch *strsrch);
|
||
|
||
#endif /* #if !UCONFIG_NO_COLLATION */
|
||
|
||
#endif
|