1510 lines
60 KiB
C++
1510 lines
60 KiB
C++
// © 2016 and later: Unicode, Inc. and others.
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// License & terms of use: http://www.unicode.org/copyright.html
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/*
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******************************************************************************
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*
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* Copyright (C) 2007-2012, International Business Machines
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* Corporation and others. All Rights Reserved.
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*
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******************************************************************************
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* file name: unisetspan.cpp
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* encoding: UTF-8
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* tab size: 8 (not used)
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* indentation:4
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*
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* created on: 2007mar01
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* created by: Markus W. Scherer
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*/
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#include "unicode/utypes.h"
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#include "unicode/uniset.h"
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#include "unicode/ustring.h"
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#include "unicode/utf8.h"
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#include "unicode/utf16.h"
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#include "cmemory.h"
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#include "uvector.h"
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#include "unisetspan.h"
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U_NAMESPACE_BEGIN
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/*
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* List of offsets from the current position from where to try matching
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* a code point or a string.
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* Store offsets rather than indexes to simplify the code and use the same list
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* for both increments (in span()) and decrements (in spanBack()).
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*
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* Assumption: The maximum offset is limited, and the offsets that are stored
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* at any one time are relatively dense, that is, there are normally no gaps of
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* hundreds or thousands of offset values.
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*
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* The implementation uses a circular buffer of byte flags,
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* each indicating whether the corresponding offset is in the list.
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* This avoids inserting into a sorted list of offsets (or absolute indexes) and
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* physically moving part of the list.
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*
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* Note: In principle, the caller should setMaxLength() to the maximum of the
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* max string length and U16_LENGTH/U8_LENGTH to account for
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* "long" single code points.
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* However, this implementation uses at least a staticList with more than
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* U8_LENGTH entries anyway.
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*
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* Note: If maxLength were guaranteed to be no more than 32 or 64,
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* the list could be stored as bit flags in a single integer.
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* Rather than handling a circular buffer with a start list index,
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* the integer would simply be shifted when lower offsets are removed.
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* UnicodeSet does not have a limit on the lengths of strings.
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*/
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class OffsetList { // Only ever stack-allocated, does not need to inherit UMemory.
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public:
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OffsetList() : list(staticList), capacity(0), length(0), start(0) {}
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~OffsetList() {
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if(list!=staticList) {
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uprv_free(list);
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}
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}
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// Call exactly once if the list is to be used.
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void setMaxLength(int32_t maxLength) {
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if(maxLength<=(int32_t)sizeof(staticList)) {
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capacity=(int32_t)sizeof(staticList);
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} else {
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UBool *l=(UBool *)uprv_malloc(maxLength);
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if(l!=NULL) {
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list=l;
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capacity=maxLength;
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}
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}
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uprv_memset(list, 0, capacity);
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}
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void clear() {
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uprv_memset(list, 0, capacity);
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start=length=0;
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}
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UBool isEmpty() const {
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return (UBool)(length==0);
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}
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// Reduce all stored offsets by delta, used when the current position
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// moves by delta.
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// There must not be any offsets lower than delta.
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// If there is an offset equal to delta, it is removed.
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// delta=[1..maxLength]
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void shift(int32_t delta) {
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int32_t i=start+delta;
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if(i>=capacity) {
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i-=capacity;
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}
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if(list[i]) {
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list[i]=FALSE;
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--length;
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}
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start=i;
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}
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// Add an offset. The list must not contain it yet.
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// offset=[1..maxLength]
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void addOffset(int32_t offset) {
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int32_t i=start+offset;
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if(i>=capacity) {
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i-=capacity;
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}
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list[i]=TRUE;
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++length;
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}
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// offset=[1..maxLength]
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UBool containsOffset(int32_t offset) const {
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int32_t i=start+offset;
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if(i>=capacity) {
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i-=capacity;
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}
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return list[i];
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}
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// Find the lowest stored offset from a non-empty list, remove it,
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// and reduce all other offsets by this minimum.
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// Returns [1..maxLength].
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int32_t popMinimum() {
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// Look for the next offset in list[start+1..capacity-1].
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int32_t i=start, result;
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while(++i<capacity) {
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if(list[i]) {
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list[i]=FALSE;
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--length;
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result=i-start;
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start=i;
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return result;
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}
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}
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// i==capacity
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// Wrap around and look for the next offset in list[0..start].
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// Since the list is not empty, there will be one.
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result=capacity-start;
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i=0;
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while(!list[i]) {
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++i;
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}
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list[i]=FALSE;
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--length;
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start=i;
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return result+=i;
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}
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private:
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UBool *list;
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int32_t capacity;
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int32_t length;
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int32_t start;
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UBool staticList[16];
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};
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// Get the number of UTF-8 bytes for a UTF-16 (sub)string.
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static int32_t
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getUTF8Length(const UChar *s, int32_t length) {
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UErrorCode errorCode=U_ZERO_ERROR;
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int32_t length8=0;
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u_strToUTF8(NULL, 0, &length8, s, length, &errorCode);
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if(U_SUCCESS(errorCode) || errorCode==U_BUFFER_OVERFLOW_ERROR) {
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return length8;
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} else {
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// The string contains an unpaired surrogate.
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// Ignore this string.
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return 0;
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}
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}
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// Append the UTF-8 version of the string to t and return the appended UTF-8 length.
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static int32_t
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appendUTF8(const UChar *s, int32_t length, uint8_t *t, int32_t capacity) {
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UErrorCode errorCode=U_ZERO_ERROR;
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int32_t length8=0;
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u_strToUTF8((char *)t, capacity, &length8, s, length, &errorCode);
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if(U_SUCCESS(errorCode)) {
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return length8;
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} else {
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// The string contains an unpaired surrogate.
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// Ignore this string.
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return 0;
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}
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}
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static inline uint8_t
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makeSpanLengthByte(int32_t spanLength) {
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// 0xfe==UnicodeSetStringSpan::LONG_SPAN
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return spanLength<0xfe ? (uint8_t)spanLength : (uint8_t)0xfe;
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}
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// Construct for all variants of span(), or only for any one variant.
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// Initialize as little as possible, for single use.
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UnicodeSetStringSpan::UnicodeSetStringSpan(const UnicodeSet &set,
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const UVector &setStrings,
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uint32_t which)
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: spanSet(0, 0x10ffff), pSpanNotSet(NULL), strings(setStrings),
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utf8Lengths(NULL), spanLengths(NULL), utf8(NULL),
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utf8Length(0),
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maxLength16(0), maxLength8(0),
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all((UBool)(which==ALL)) {
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spanSet.retainAll(set);
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if(which&NOT_CONTAINED) {
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// Default to the same sets.
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// addToSpanNotSet() will create a separate set if necessary.
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pSpanNotSet=&spanSet;
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}
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// Determine if the strings even need to be taken into account at all for span() etc.
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// If any string is relevant, then all strings need to be used for
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// span(longest match) but only the relevant ones for span(while contained).
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// TODO: Possible optimization: Distinguish CONTAINED vs. LONGEST_MATCH
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// and do not store UTF-8 strings if !thisRelevant and CONTAINED.
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// (Only store irrelevant UTF-8 strings for LONGEST_MATCH where they are relevant after all.)
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// Also count the lengths of the UTF-8 versions of the strings for memory allocation.
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int32_t stringsLength=strings.size();
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int32_t i, spanLength;
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UBool someRelevant=FALSE;
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for(i=0; i<stringsLength; ++i) {
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const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
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const UChar *s16=string.getBuffer();
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int32_t length16=string.length();
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UBool thisRelevant;
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spanLength=spanSet.span(s16, length16, USET_SPAN_CONTAINED);
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if(spanLength<length16) { // Relevant string.
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someRelevant=thisRelevant=TRUE;
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} else {
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thisRelevant=FALSE;
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}
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if((which&UTF16) && length16>maxLength16) {
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maxLength16=length16;
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}
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if((which&UTF8) && (thisRelevant || (which&CONTAINED))) {
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int32_t length8=getUTF8Length(s16, length16);
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utf8Length+=length8;
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if(length8>maxLength8) {
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maxLength8=length8;
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}
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}
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}
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if(!someRelevant) {
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maxLength16=maxLength8=0;
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return;
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}
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// Freeze after checking for the need to use strings at all because freezing
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// a set takes some time and memory which are wasted if there are no relevant strings.
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if(all) {
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spanSet.freeze();
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}
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uint8_t *spanBackLengths;
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uint8_t *spanUTF8Lengths;
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uint8_t *spanBackUTF8Lengths;
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// Allocate a block of meta data.
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int32_t allocSize;
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if(all) {
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// UTF-8 lengths, 4 sets of span lengths, UTF-8 strings.
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allocSize=stringsLength*(4+1+1+1+1)+utf8Length;
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} else {
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allocSize=stringsLength; // One set of span lengths.
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if(which&UTF8) {
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// UTF-8 lengths and UTF-8 strings.
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allocSize+=stringsLength*4+utf8Length;
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}
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}
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if(allocSize<=(int32_t)sizeof(staticLengths)) {
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utf8Lengths=staticLengths;
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} else {
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utf8Lengths=(int32_t *)uprv_malloc(allocSize);
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if(utf8Lengths==NULL) {
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maxLength16=maxLength8=0; // Prevent usage by making needsStringSpanUTF16/8() return FALSE.
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return; // Out of memory.
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}
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}
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if(all) {
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// Store span lengths for all span() variants.
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spanLengths=(uint8_t *)(utf8Lengths+stringsLength);
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spanBackLengths=spanLengths+stringsLength;
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spanUTF8Lengths=spanBackLengths+stringsLength;
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spanBackUTF8Lengths=spanUTF8Lengths+stringsLength;
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utf8=spanBackUTF8Lengths+stringsLength;
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} else {
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// Store span lengths for only one span() variant.
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if(which&UTF8) {
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spanLengths=(uint8_t *)(utf8Lengths+stringsLength);
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utf8=spanLengths+stringsLength;
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} else {
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spanLengths=(uint8_t *)utf8Lengths;
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}
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spanBackLengths=spanUTF8Lengths=spanBackUTF8Lengths=spanLengths;
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}
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// Set the meta data and pSpanNotSet and write the UTF-8 strings.
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int32_t utf8Count=0; // Count UTF-8 bytes written so far.
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for(i=0; i<stringsLength; ++i) {
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const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
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const UChar *s16=string.getBuffer();
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int32_t length16=string.length();
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spanLength=spanSet.span(s16, length16, USET_SPAN_CONTAINED);
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if(spanLength<length16) { // Relevant string.
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if(which&UTF16) {
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if(which&CONTAINED) {
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if(which&FWD) {
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spanLengths[i]=makeSpanLengthByte(spanLength);
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}
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if(which&BACK) {
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spanLength=length16-spanSet.spanBack(s16, length16, USET_SPAN_CONTAINED);
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spanBackLengths[i]=makeSpanLengthByte(spanLength);
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}
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} else /* not CONTAINED, not all, but NOT_CONTAINED */ {
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spanLengths[i]=spanBackLengths[i]=0; // Only store a relevant/irrelevant flag.
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}
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}
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if(which&UTF8) {
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uint8_t *s8=utf8+utf8Count;
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int32_t length8=appendUTF8(s16, length16, s8, utf8Length-utf8Count);
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utf8Count+=utf8Lengths[i]=length8;
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if(length8==0) { // Irrelevant for UTF-8 because not representable in UTF-8.
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spanUTF8Lengths[i]=spanBackUTF8Lengths[i]=(uint8_t)ALL_CP_CONTAINED;
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} else { // Relevant for UTF-8.
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if(which&CONTAINED) {
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if(which&FWD) {
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spanLength=spanSet.spanUTF8((const char *)s8, length8, USET_SPAN_CONTAINED);
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spanUTF8Lengths[i]=makeSpanLengthByte(spanLength);
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}
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if(which&BACK) {
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spanLength=length8-spanSet.spanBackUTF8((const char *)s8, length8, USET_SPAN_CONTAINED);
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spanBackUTF8Lengths[i]=makeSpanLengthByte(spanLength);
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}
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} else /* not CONTAINED, not all, but NOT_CONTAINED */ {
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spanUTF8Lengths[i]=spanBackUTF8Lengths[i]=0; // Only store a relevant/irrelevant flag.
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}
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}
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}
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if(which&NOT_CONTAINED) {
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// Add string start and end code points to the spanNotSet so that
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// a span(while not contained) stops before any string.
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UChar32 c;
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if(which&FWD) {
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int32_t len=0;
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U16_NEXT(s16, len, length16, c);
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addToSpanNotSet(c);
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}
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if(which&BACK) {
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int32_t len=length16;
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U16_PREV(s16, 0, len, c);
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addToSpanNotSet(c);
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}
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}
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} else { // Irrelevant string.
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if(which&UTF8) {
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if(which&CONTAINED) { // Only necessary for LONGEST_MATCH.
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uint8_t *s8=utf8+utf8Count;
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int32_t length8=appendUTF8(s16, length16, s8, utf8Length-utf8Count);
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utf8Count+=utf8Lengths[i]=length8;
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} else {
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utf8Lengths[i]=0;
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}
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}
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if(all) {
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spanLengths[i]=spanBackLengths[i]=
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spanUTF8Lengths[i]=spanBackUTF8Lengths[i]=
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(uint8_t)ALL_CP_CONTAINED;
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} else {
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// All spanXYZLengths pointers contain the same address.
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spanLengths[i]=(uint8_t)ALL_CP_CONTAINED;
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}
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}
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}
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// Finish.
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if(all) {
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pSpanNotSet->freeze();
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}
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}
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// Copy constructor. Assumes which==ALL for a frozen set.
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UnicodeSetStringSpan::UnicodeSetStringSpan(const UnicodeSetStringSpan &otherStringSpan,
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const UVector &newParentSetStrings)
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: spanSet(otherStringSpan.spanSet), pSpanNotSet(NULL), strings(newParentSetStrings),
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utf8Lengths(NULL), spanLengths(NULL), utf8(NULL),
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utf8Length(otherStringSpan.utf8Length),
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maxLength16(otherStringSpan.maxLength16), maxLength8(otherStringSpan.maxLength8),
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all(TRUE) {
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if(otherStringSpan.pSpanNotSet==&otherStringSpan.spanSet) {
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pSpanNotSet=&spanSet;
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} else {
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pSpanNotSet=otherStringSpan.pSpanNotSet->clone();
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}
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// Allocate a block of meta data.
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// UTF-8 lengths, 4 sets of span lengths, UTF-8 strings.
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int32_t stringsLength=strings.size();
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int32_t allocSize=stringsLength*(4+1+1+1+1)+utf8Length;
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if(allocSize<=(int32_t)sizeof(staticLengths)) {
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utf8Lengths=staticLengths;
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} else {
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utf8Lengths=(int32_t *)uprv_malloc(allocSize);
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if(utf8Lengths==NULL) {
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maxLength16=maxLength8=0; // Prevent usage by making needsStringSpanUTF16/8() return FALSE.
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return; // Out of memory.
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}
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}
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spanLengths=(uint8_t *)(utf8Lengths+stringsLength);
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utf8=spanLengths+stringsLength*4;
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uprv_memcpy(utf8Lengths, otherStringSpan.utf8Lengths, allocSize);
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}
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UnicodeSetStringSpan::~UnicodeSetStringSpan() {
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if(pSpanNotSet!=NULL && pSpanNotSet!=&spanSet) {
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delete pSpanNotSet;
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}
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if(utf8Lengths!=NULL && utf8Lengths!=staticLengths) {
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uprv_free(utf8Lengths);
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}
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}
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void UnicodeSetStringSpan::addToSpanNotSet(UChar32 c) {
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if(pSpanNotSet==NULL || pSpanNotSet==&spanSet) {
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if(spanSet.contains(c)) {
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return; // Nothing to do.
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}
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UnicodeSet *newSet=spanSet.cloneAsThawed();
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if(newSet==NULL) {
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return; // Out of memory.
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} else {
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pSpanNotSet=newSet;
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}
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}
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pSpanNotSet->add(c);
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}
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// Compare strings without any argument checks. Requires length>0.
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static inline UBool
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matches16(const UChar *s, const UChar *t, int32_t length) {
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do {
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if(*s++!=*t++) {
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return FALSE;
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}
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} while(--length>0);
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return TRUE;
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}
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static inline UBool
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matches8(const uint8_t *s, const uint8_t *t, int32_t length) {
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do {
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if(*s++!=*t++) {
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return FALSE;
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}
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} while(--length>0);
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return TRUE;
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}
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// Compare 16-bit Unicode strings (which may be malformed UTF-16)
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// at code point boundaries.
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// That is, each edge of a match must not be in the middle of a surrogate pair.
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static inline UBool
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matches16CPB(const UChar *s, int32_t start, int32_t limit, const UChar *t, int32_t length) {
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s+=start;
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limit-=start;
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return matches16(s, t, length) &&
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!(0<start && U16_IS_LEAD(s[-1]) && U16_IS_TRAIL(s[0])) &&
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!(length<limit && U16_IS_LEAD(s[length-1]) && U16_IS_TRAIL(s[length]));
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}
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// Does the set contain the next code point?
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// If so, return its length; otherwise return its negative length.
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static inline int32_t
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spanOne(const UnicodeSet &set, const UChar *s, int32_t length) {
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UChar c=*s, c2;
|
|
if(c>=0xd800 && c<=0xdbff && length>=2 && U16_IS_TRAIL(c2=s[1])) {
|
|
return set.contains(U16_GET_SUPPLEMENTARY(c, c2)) ? 2 : -2;
|
|
}
|
|
return set.contains(c) ? 1 : -1;
|
|
}
|
|
|
|
static inline int32_t
|
|
spanOneBack(const UnicodeSet &set, const UChar *s, int32_t length) {
|
|
UChar c=s[length-1], c2;
|
|
if(c>=0xdc00 && c<=0xdfff && length>=2 && U16_IS_LEAD(c2=s[length-2])) {
|
|
return set.contains(U16_GET_SUPPLEMENTARY(c2, c)) ? 2 : -2;
|
|
}
|
|
return set.contains(c) ? 1 : -1;
|
|
}
|
|
|
|
static inline int32_t
|
|
spanOneUTF8(const UnicodeSet &set, const uint8_t *s, int32_t length) {
|
|
UChar32 c=*s;
|
|
if(U8_IS_SINGLE(c)) {
|
|
return set.contains(c) ? 1 : -1;
|
|
}
|
|
// Take advantage of non-ASCII fastpaths in U8_NEXT_OR_FFFD().
|
|
int32_t i=0;
|
|
U8_NEXT_OR_FFFD(s, i, length, c);
|
|
return set.contains(c) ? i : -i;
|
|
}
|
|
|
|
static inline int32_t
|
|
spanOneBackUTF8(const UnicodeSet &set, const uint8_t *s, int32_t length) {
|
|
UChar32 c=s[length-1];
|
|
if(U8_IS_SINGLE(c)) {
|
|
return set.contains(c) ? 1 : -1;
|
|
}
|
|
int32_t i=length-1;
|
|
c=utf8_prevCharSafeBody(s, 0, &i, c, -3);
|
|
length-=i;
|
|
return set.contains(c) ? length : -length;
|
|
}
|
|
|
|
/*
|
|
* Note: In span() when spanLength==0 (after a string match, or at the beginning
|
|
* after an empty code point span) and in spanNot() and spanNotUTF8(),
|
|
* string matching could use a binary search
|
|
* because all string matches are done from the same start index.
|
|
*
|
|
* For UTF-8, this would require a comparison function that returns UTF-16 order.
|
|
*
|
|
* This optimization should not be necessary for normal UnicodeSets because
|
|
* most sets have no strings, and most sets with strings have
|
|
* very few very short strings.
|
|
* For cases with many strings, it might be better to use a different API
|
|
* and implementation with a DFA (state machine).
|
|
*/
|
|
|
|
/*
|
|
* Algorithm for span(USET_SPAN_CONTAINED)
|
|
*
|
|
* Theoretical algorithm:
|
|
* - Iterate through the string, and at each code point boundary:
|
|
* + If the code point there is in the set, then remember to continue after it.
|
|
* + If a set string matches at the current position, then remember to continue after it.
|
|
* + Either recursively span for each code point or string match,
|
|
* or recursively span for all but the shortest one and
|
|
* iteratively continue the span with the shortest local match.
|
|
* + Remember the longest recursive span (the farthest end point).
|
|
* + If there is no match at the current position, neither for the code point there
|
|
* nor for any set string, then stop and return the longest recursive span length.
|
|
*
|
|
* Optimized implementation:
|
|
*
|
|
* (We assume that most sets will have very few very short strings.
|
|
* A span using a string-less set is extremely fast.)
|
|
*
|
|
* Create and cache a spanSet which contains all of the single code points
|
|
* of the original set but none of its strings.
|
|
*
|
|
* - Start with spanLength=spanSet.span(USET_SPAN_CONTAINED).
|
|
* - Loop:
|
|
* + Try to match each set string at the end of the spanLength.
|
|
* ~ Set strings that start with set-contained code points must be matched
|
|
* with a partial overlap because the recursive algorithm would have tried
|
|
* to match them at every position.
|
|
* ~ Set strings that entirely consist of set-contained code points
|
|
* are irrelevant for span(USET_SPAN_CONTAINED) because the
|
|
* recursive algorithm would continue after them anyway
|
|
* and find the longest recursive match from their end.
|
|
* ~ Rather than recursing, note each end point of a set string match.
|
|
* + If no set string matched after spanSet.span(), then return
|
|
* with where the spanSet.span() ended.
|
|
* + If at least one set string matched after spanSet.span(), then
|
|
* pop the shortest string match end point and continue
|
|
* the loop, trying to match all set strings from there.
|
|
* + If at least one more set string matched after a previous string match,
|
|
* then test if the code point after the previous string match is also
|
|
* contained in the set.
|
|
* Continue the loop with the shortest end point of either this code point
|
|
* or a matching set string.
|
|
* + If no more set string matched after a previous string match,
|
|
* then try another spanLength=spanSet.span(USET_SPAN_CONTAINED).
|
|
* Stop if spanLength==0, otherwise continue the loop.
|
|
*
|
|
* By noting each end point of a set string match,
|
|
* the function visits each string position at most once and finishes
|
|
* in linear time.
|
|
*
|
|
* The recursive algorithm may visit the same string position many times
|
|
* if multiple paths lead to it and finishes in exponential time.
|
|
*/
|
|
|
|
/*
|
|
* Algorithm for span(USET_SPAN_SIMPLE)
|
|
*
|
|
* Theoretical algorithm:
|
|
* - Iterate through the string, and at each code point boundary:
|
|
* + If the code point there is in the set, then remember to continue after it.
|
|
* + If a set string matches at the current position, then remember to continue after it.
|
|
* + Continue from the farthest match position and ignore all others.
|
|
* + If there is no match at the current position,
|
|
* then stop and return the current position.
|
|
*
|
|
* Optimized implementation:
|
|
*
|
|
* (Same assumption and spanSet as above.)
|
|
*
|
|
* - Start with spanLength=spanSet.span(USET_SPAN_CONTAINED).
|
|
* - Loop:
|
|
* + Try to match each set string at the end of the spanLength.
|
|
* ~ Set strings that start with set-contained code points must be matched
|
|
* with a partial overlap because the standard algorithm would have tried
|
|
* to match them earlier.
|
|
* ~ Set strings that entirely consist of set-contained code points
|
|
* must be matched with a full overlap because the longest-match algorithm
|
|
* would hide set string matches that end earlier.
|
|
* Such set strings need not be matched earlier inside the code point span
|
|
* because the standard algorithm would then have continued after
|
|
* the set string match anyway.
|
|
* ~ Remember the longest set string match (farthest end point) from the earliest
|
|
* starting point.
|
|
* + If no set string matched after spanSet.span(), then return
|
|
* with where the spanSet.span() ended.
|
|
* + If at least one set string matched, then continue the loop after the
|
|
* longest match from the earliest position.
|
|
* + If no more set string matched after a previous string match,
|
|
* then try another spanLength=spanSet.span(USET_SPAN_CONTAINED).
|
|
* Stop if spanLength==0, otherwise continue the loop.
|
|
*/
|
|
|
|
int32_t UnicodeSetStringSpan::span(const UChar *s, int32_t length, USetSpanCondition spanCondition) const {
|
|
if(spanCondition==USET_SPAN_NOT_CONTAINED) {
|
|
return spanNot(s, length);
|
|
}
|
|
int32_t spanLength=spanSet.span(s, length, USET_SPAN_CONTAINED);
|
|
if(spanLength==length) {
|
|
return length;
|
|
}
|
|
|
|
// Consider strings; they may overlap with the span.
|
|
OffsetList offsets;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
// Use offset list to try all possibilities.
|
|
offsets.setMaxLength(maxLength16);
|
|
}
|
|
int32_t pos=spanLength, rest=length-pos;
|
|
int32_t i, stringsLength=strings.size();
|
|
for(;;) {
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
for(i=0; i<stringsLength; ++i) {
|
|
int32_t overlap=spanLengths[i];
|
|
if(overlap==ALL_CP_CONTAINED) {
|
|
continue; // Irrelevant string.
|
|
}
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
|
|
// Try to match this string at pos-overlap..pos.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length16;
|
|
// While contained: No point matching fully inside the code point span.
|
|
U16_BACK_1(s16, 0, overlap); // Length of the string minus the last code point.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t inc=length16-overlap; // Keep overlap+inc==length16.
|
|
for(;;) {
|
|
if(inc>rest) {
|
|
break;
|
|
}
|
|
// Try to match if the increment is not listed already.
|
|
if(!offsets.containsOffset(inc) && matches16CPB(s, pos-overlap, length, s16, length16)) {
|
|
if(inc==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
offsets.addOffset(inc);
|
|
}
|
|
if(overlap==0) {
|
|
break;
|
|
}
|
|
--overlap;
|
|
++inc;
|
|
}
|
|
}
|
|
} else /* USET_SPAN_SIMPLE */ {
|
|
int32_t maxInc=0, maxOverlap=0;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
int32_t overlap=spanLengths[i];
|
|
// For longest match, we do need to try to match even an all-contained string
|
|
// to find the match from the earliest start.
|
|
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
|
|
// Try to match this string at pos-overlap..pos.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length16;
|
|
// Longest match: Need to match fully inside the code point span
|
|
// to find the match from the earliest start.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t inc=length16-overlap; // Keep overlap+inc==length16.
|
|
for(;;) {
|
|
if(inc>rest || overlap<maxOverlap) {
|
|
break;
|
|
}
|
|
// Try to match if the string is longer or starts earlier.
|
|
if( (overlap>maxOverlap || /* redundant overlap==maxOverlap && */ inc>maxInc) &&
|
|
matches16CPB(s, pos-overlap, length, s16, length16)
|
|
) {
|
|
maxInc=inc; // Longest match from earliest start.
|
|
maxOverlap=overlap;
|
|
break;
|
|
}
|
|
--overlap;
|
|
++inc;
|
|
}
|
|
}
|
|
|
|
if(maxInc!=0 || maxOverlap!=0) {
|
|
// Longest-match algorithm, and there was a string match.
|
|
// Simply continue after it.
|
|
pos+=maxInc;
|
|
rest-=maxInc;
|
|
if(rest==0) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
spanLength=0; // Match strings from after a string match.
|
|
continue;
|
|
}
|
|
}
|
|
// Finished trying to match all strings at pos.
|
|
|
|
if(spanLength!=0 || pos==0) {
|
|
// The position is after an unlimited code point span (spanLength!=0),
|
|
// not after a string match.
|
|
// The only position where spanLength==0 after a span is pos==0.
|
|
// Otherwise, an unlimited code point span is only tried again when no
|
|
// strings match, and if such a non-initial span fails we stop.
|
|
if(offsets.isEmpty()) {
|
|
return pos; // No strings matched after a span.
|
|
}
|
|
// Match strings from after the next string match.
|
|
} else {
|
|
// The position is after a string match (or a single code point).
|
|
if(offsets.isEmpty()) {
|
|
// No more strings matched after a previous string match.
|
|
// Try another code point span from after the last string match.
|
|
spanLength=spanSet.span(s+pos, rest, USET_SPAN_CONTAINED);
|
|
if( spanLength==rest || // Reached the end of the string, or
|
|
spanLength==0 // neither strings nor span progressed.
|
|
) {
|
|
return pos+spanLength;
|
|
}
|
|
pos+=spanLength;
|
|
rest-=spanLength;
|
|
continue; // spanLength>0: Match strings from after a span.
|
|
} else {
|
|
// Try to match only one code point from after a string match if some
|
|
// string matched beyond it, so that we try all possible positions
|
|
// and don't overshoot.
|
|
spanLength=spanOne(spanSet, s+pos, rest);
|
|
if(spanLength>0) {
|
|
if(spanLength==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
// Match strings after this code point.
|
|
// There cannot be any increments below it because UnicodeSet strings
|
|
// contain multiple code points.
|
|
pos+=spanLength;
|
|
rest-=spanLength;
|
|
offsets.shift(spanLength);
|
|
spanLength=0;
|
|
continue; // Match strings from after a single code point.
|
|
}
|
|
// Match strings from after the next string match.
|
|
}
|
|
}
|
|
int32_t minOffset=offsets.popMinimum();
|
|
pos+=minOffset;
|
|
rest-=minOffset;
|
|
spanLength=0; // Match strings from after a string match.
|
|
}
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanBack(const UChar *s, int32_t length, USetSpanCondition spanCondition) const {
|
|
if(spanCondition==USET_SPAN_NOT_CONTAINED) {
|
|
return spanNotBack(s, length);
|
|
}
|
|
int32_t pos=spanSet.spanBack(s, length, USET_SPAN_CONTAINED);
|
|
if(pos==0) {
|
|
return 0;
|
|
}
|
|
int32_t spanLength=length-pos;
|
|
|
|
// Consider strings; they may overlap with the span.
|
|
OffsetList offsets;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
// Use offset list to try all possibilities.
|
|
offsets.setMaxLength(maxLength16);
|
|
}
|
|
int32_t i, stringsLength=strings.size();
|
|
uint8_t *spanBackLengths=spanLengths;
|
|
if(all) {
|
|
spanBackLengths+=stringsLength;
|
|
}
|
|
for(;;) {
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
for(i=0; i<stringsLength; ++i) {
|
|
int32_t overlap=spanBackLengths[i];
|
|
if(overlap==ALL_CP_CONTAINED) {
|
|
continue; // Irrelevant string.
|
|
}
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
|
|
// Try to match this string at pos-(length16-overlap)..pos-length16.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length16;
|
|
// While contained: No point matching fully inside the code point span.
|
|
int32_t len1=0;
|
|
U16_FWD_1(s16, len1, overlap);
|
|
overlap-=len1; // Length of the string minus the first code point.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t dec=length16-overlap; // Keep dec+overlap==length16.
|
|
for(;;) {
|
|
if(dec>pos) {
|
|
break;
|
|
}
|
|
// Try to match if the decrement is not listed already.
|
|
if(!offsets.containsOffset(dec) && matches16CPB(s, pos-dec, length, s16, length16)) {
|
|
if(dec==pos) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
offsets.addOffset(dec);
|
|
}
|
|
if(overlap==0) {
|
|
break;
|
|
}
|
|
--overlap;
|
|
++dec;
|
|
}
|
|
}
|
|
} else /* USET_SPAN_SIMPLE */ {
|
|
int32_t maxDec=0, maxOverlap=0;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
int32_t overlap=spanBackLengths[i];
|
|
// For longest match, we do need to try to match even an all-contained string
|
|
// to find the match from the latest end.
|
|
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
|
|
// Try to match this string at pos-(length16-overlap)..pos-length16.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length16;
|
|
// Longest match: Need to match fully inside the code point span
|
|
// to find the match from the latest end.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t dec=length16-overlap; // Keep dec+overlap==length16.
|
|
for(;;) {
|
|
if(dec>pos || overlap<maxOverlap) {
|
|
break;
|
|
}
|
|
// Try to match if the string is longer or ends later.
|
|
if( (overlap>maxOverlap || /* redundant overlap==maxOverlap && */ dec>maxDec) &&
|
|
matches16CPB(s, pos-dec, length, s16, length16)
|
|
) {
|
|
maxDec=dec; // Longest match from latest end.
|
|
maxOverlap=overlap;
|
|
break;
|
|
}
|
|
--overlap;
|
|
++dec;
|
|
}
|
|
}
|
|
|
|
if(maxDec!=0 || maxOverlap!=0) {
|
|
// Longest-match algorithm, and there was a string match.
|
|
// Simply continue before it.
|
|
pos-=maxDec;
|
|
if(pos==0) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
spanLength=0; // Match strings from before a string match.
|
|
continue;
|
|
}
|
|
}
|
|
// Finished trying to match all strings at pos.
|
|
|
|
if(spanLength!=0 || pos==length) {
|
|
// The position is before an unlimited code point span (spanLength!=0),
|
|
// not before a string match.
|
|
// The only position where spanLength==0 before a span is pos==length.
|
|
// Otherwise, an unlimited code point span is only tried again when no
|
|
// strings match, and if such a non-initial span fails we stop.
|
|
if(offsets.isEmpty()) {
|
|
return pos; // No strings matched before a span.
|
|
}
|
|
// Match strings from before the next string match.
|
|
} else {
|
|
// The position is before a string match (or a single code point).
|
|
if(offsets.isEmpty()) {
|
|
// No more strings matched before a previous string match.
|
|
// Try another code point span from before the last string match.
|
|
int32_t oldPos=pos;
|
|
pos=spanSet.spanBack(s, oldPos, USET_SPAN_CONTAINED);
|
|
spanLength=oldPos-pos;
|
|
if( pos==0 || // Reached the start of the string, or
|
|
spanLength==0 // neither strings nor span progressed.
|
|
) {
|
|
return pos;
|
|
}
|
|
continue; // spanLength>0: Match strings from before a span.
|
|
} else {
|
|
// Try to match only one code point from before a string match if some
|
|
// string matched beyond it, so that we try all possible positions
|
|
// and don't overshoot.
|
|
spanLength=spanOneBack(spanSet, s, pos);
|
|
if(spanLength>0) {
|
|
if(spanLength==pos) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
// Match strings before this code point.
|
|
// There cannot be any decrements below it because UnicodeSet strings
|
|
// contain multiple code points.
|
|
pos-=spanLength;
|
|
offsets.shift(spanLength);
|
|
spanLength=0;
|
|
continue; // Match strings from before a single code point.
|
|
}
|
|
// Match strings from before the next string match.
|
|
}
|
|
}
|
|
pos-=offsets.popMinimum();
|
|
spanLength=0; // Match strings from before a string match.
|
|
}
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
|
|
if(spanCondition==USET_SPAN_NOT_CONTAINED) {
|
|
return spanNotUTF8(s, length);
|
|
}
|
|
int32_t spanLength=spanSet.spanUTF8((const char *)s, length, USET_SPAN_CONTAINED);
|
|
if(spanLength==length) {
|
|
return length;
|
|
}
|
|
|
|
// Consider strings; they may overlap with the span.
|
|
OffsetList offsets;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
// Use offset list to try all possibilities.
|
|
offsets.setMaxLength(maxLength8);
|
|
}
|
|
int32_t pos=spanLength, rest=length-pos;
|
|
int32_t i, stringsLength=strings.size();
|
|
uint8_t *spanUTF8Lengths=spanLengths;
|
|
if(all) {
|
|
spanUTF8Lengths+=2*stringsLength;
|
|
}
|
|
for(;;) {
|
|
const uint8_t *s8=utf8;
|
|
int32_t length8;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
if(length8==0) {
|
|
continue; // String not representable in UTF-8.
|
|
}
|
|
int32_t overlap=spanUTF8Lengths[i];
|
|
if(overlap==ALL_CP_CONTAINED) {
|
|
s8+=length8;
|
|
continue; // Irrelevant string.
|
|
}
|
|
|
|
// Try to match this string at pos-overlap..pos.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length8;
|
|
// While contained: No point matching fully inside the code point span.
|
|
U8_BACK_1(s8, 0, overlap); // Length of the string minus the last code point.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t inc=length8-overlap; // Keep overlap+inc==length8.
|
|
for(;;) {
|
|
if(inc>rest) {
|
|
break;
|
|
}
|
|
// Try to match if the increment is not listed already.
|
|
// Match at code point boundaries. (The UTF-8 strings were converted
|
|
// from UTF-16 and are guaranteed to be well-formed.)
|
|
if(!U8_IS_TRAIL(s[pos-overlap]) &&
|
|
!offsets.containsOffset(inc) &&
|
|
matches8(s+pos-overlap, s8, length8)) {
|
|
if(inc==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
offsets.addOffset(inc);
|
|
}
|
|
if(overlap==0) {
|
|
break;
|
|
}
|
|
--overlap;
|
|
++inc;
|
|
}
|
|
s8+=length8;
|
|
}
|
|
} else /* USET_SPAN_SIMPLE */ {
|
|
int32_t maxInc=0, maxOverlap=0;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
if(length8==0) {
|
|
continue; // String not representable in UTF-8.
|
|
}
|
|
int32_t overlap=spanUTF8Lengths[i];
|
|
// For longest match, we do need to try to match even an all-contained string
|
|
// to find the match from the earliest start.
|
|
|
|
// Try to match this string at pos-overlap..pos.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length8;
|
|
// Longest match: Need to match fully inside the code point span
|
|
// to find the match from the earliest start.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t inc=length8-overlap; // Keep overlap+inc==length8.
|
|
for(;;) {
|
|
if(inc>rest || overlap<maxOverlap) {
|
|
break;
|
|
}
|
|
// Try to match if the string is longer or starts earlier.
|
|
// Match at code point boundaries. (The UTF-8 strings were converted
|
|
// from UTF-16 and are guaranteed to be well-formed.)
|
|
if(!U8_IS_TRAIL(s[pos-overlap]) &&
|
|
(overlap>maxOverlap ||
|
|
/* redundant overlap==maxOverlap && */ inc>maxInc) &&
|
|
matches8(s+pos-overlap, s8, length8)) {
|
|
maxInc=inc; // Longest match from earliest start.
|
|
maxOverlap=overlap;
|
|
break;
|
|
}
|
|
--overlap;
|
|
++inc;
|
|
}
|
|
s8+=length8;
|
|
}
|
|
|
|
if(maxInc!=0 || maxOverlap!=0) {
|
|
// Longest-match algorithm, and there was a string match.
|
|
// Simply continue after it.
|
|
pos+=maxInc;
|
|
rest-=maxInc;
|
|
if(rest==0) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
spanLength=0; // Match strings from after a string match.
|
|
continue;
|
|
}
|
|
}
|
|
// Finished trying to match all strings at pos.
|
|
|
|
if(spanLength!=0 || pos==0) {
|
|
// The position is after an unlimited code point span (spanLength!=0),
|
|
// not after a string match.
|
|
// The only position where spanLength==0 after a span is pos==0.
|
|
// Otherwise, an unlimited code point span is only tried again when no
|
|
// strings match, and if such a non-initial span fails we stop.
|
|
if(offsets.isEmpty()) {
|
|
return pos; // No strings matched after a span.
|
|
}
|
|
// Match strings from after the next string match.
|
|
} else {
|
|
// The position is after a string match (or a single code point).
|
|
if(offsets.isEmpty()) {
|
|
// No more strings matched after a previous string match.
|
|
// Try another code point span from after the last string match.
|
|
spanLength=spanSet.spanUTF8((const char *)s+pos, rest, USET_SPAN_CONTAINED);
|
|
if( spanLength==rest || // Reached the end of the string, or
|
|
spanLength==0 // neither strings nor span progressed.
|
|
) {
|
|
return pos+spanLength;
|
|
}
|
|
pos+=spanLength;
|
|
rest-=spanLength;
|
|
continue; // spanLength>0: Match strings from after a span.
|
|
} else {
|
|
// Try to match only one code point from after a string match if some
|
|
// string matched beyond it, so that we try all possible positions
|
|
// and don't overshoot.
|
|
spanLength=spanOneUTF8(spanSet, s+pos, rest);
|
|
if(spanLength>0) {
|
|
if(spanLength==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
// Match strings after this code point.
|
|
// There cannot be any increments below it because UnicodeSet strings
|
|
// contain multiple code points.
|
|
pos+=spanLength;
|
|
rest-=spanLength;
|
|
offsets.shift(spanLength);
|
|
spanLength=0;
|
|
continue; // Match strings from after a single code point.
|
|
}
|
|
// Match strings from after the next string match.
|
|
}
|
|
}
|
|
int32_t minOffset=offsets.popMinimum();
|
|
pos+=minOffset;
|
|
rest-=minOffset;
|
|
spanLength=0; // Match strings from after a string match.
|
|
}
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
|
|
if(spanCondition==USET_SPAN_NOT_CONTAINED) {
|
|
return spanNotBackUTF8(s, length);
|
|
}
|
|
int32_t pos=spanSet.spanBackUTF8((const char *)s, length, USET_SPAN_CONTAINED);
|
|
if(pos==0) {
|
|
return 0;
|
|
}
|
|
int32_t spanLength=length-pos;
|
|
|
|
// Consider strings; they may overlap with the span.
|
|
OffsetList offsets;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
// Use offset list to try all possibilities.
|
|
offsets.setMaxLength(maxLength8);
|
|
}
|
|
int32_t i, stringsLength=strings.size();
|
|
uint8_t *spanBackUTF8Lengths=spanLengths;
|
|
if(all) {
|
|
spanBackUTF8Lengths+=3*stringsLength;
|
|
}
|
|
for(;;) {
|
|
const uint8_t *s8=utf8;
|
|
int32_t length8;
|
|
if(spanCondition==USET_SPAN_CONTAINED) {
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
if(length8==0) {
|
|
continue; // String not representable in UTF-8.
|
|
}
|
|
int32_t overlap=spanBackUTF8Lengths[i];
|
|
if(overlap==ALL_CP_CONTAINED) {
|
|
s8+=length8;
|
|
continue; // Irrelevant string.
|
|
}
|
|
|
|
// Try to match this string at pos-(length8-overlap)..pos-length8.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length8;
|
|
// While contained: No point matching fully inside the code point span.
|
|
int32_t len1=0;
|
|
U8_FWD_1(s8, len1, overlap);
|
|
overlap-=len1; // Length of the string minus the first code point.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t dec=length8-overlap; // Keep dec+overlap==length8.
|
|
for(;;) {
|
|
if(dec>pos) {
|
|
break;
|
|
}
|
|
// Try to match if the decrement is not listed already.
|
|
// Match at code point boundaries. (The UTF-8 strings were converted
|
|
// from UTF-16 and are guaranteed to be well-formed.)
|
|
if( !U8_IS_TRAIL(s[pos-dec]) &&
|
|
!offsets.containsOffset(dec) &&
|
|
matches8(s+pos-dec, s8, length8)
|
|
) {
|
|
if(dec==pos) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
offsets.addOffset(dec);
|
|
}
|
|
if(overlap==0) {
|
|
break;
|
|
}
|
|
--overlap;
|
|
++dec;
|
|
}
|
|
s8+=length8;
|
|
}
|
|
} else /* USET_SPAN_SIMPLE */ {
|
|
int32_t maxDec=0, maxOverlap=0;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
if(length8==0) {
|
|
continue; // String not representable in UTF-8.
|
|
}
|
|
int32_t overlap=spanBackUTF8Lengths[i];
|
|
// For longest match, we do need to try to match even an all-contained string
|
|
// to find the match from the latest end.
|
|
|
|
// Try to match this string at pos-(length8-overlap)..pos-length8.
|
|
if(overlap>=LONG_SPAN) {
|
|
overlap=length8;
|
|
// Longest match: Need to match fully inside the code point span
|
|
// to find the match from the latest end.
|
|
}
|
|
if(overlap>spanLength) {
|
|
overlap=spanLength;
|
|
}
|
|
int32_t dec=length8-overlap; // Keep dec+overlap==length8.
|
|
for(;;) {
|
|
if(dec>pos || overlap<maxOverlap) {
|
|
break;
|
|
}
|
|
// Try to match if the string is longer or ends later.
|
|
// Match at code point boundaries. (The UTF-8 strings were converted
|
|
// from UTF-16 and are guaranteed to be well-formed.)
|
|
if( !U8_IS_TRAIL(s[pos-dec]) &&
|
|
(overlap>maxOverlap || /* redundant overlap==maxOverlap && */ dec>maxDec) &&
|
|
matches8(s+pos-dec, s8, length8)
|
|
) {
|
|
maxDec=dec; // Longest match from latest end.
|
|
maxOverlap=overlap;
|
|
break;
|
|
}
|
|
--overlap;
|
|
++dec;
|
|
}
|
|
s8+=length8;
|
|
}
|
|
|
|
if(maxDec!=0 || maxOverlap!=0) {
|
|
// Longest-match algorithm, and there was a string match.
|
|
// Simply continue before it.
|
|
pos-=maxDec;
|
|
if(pos==0) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
spanLength=0; // Match strings from before a string match.
|
|
continue;
|
|
}
|
|
}
|
|
// Finished trying to match all strings at pos.
|
|
|
|
if(spanLength!=0 || pos==length) {
|
|
// The position is before an unlimited code point span (spanLength!=0),
|
|
// not before a string match.
|
|
// The only position where spanLength==0 before a span is pos==length.
|
|
// Otherwise, an unlimited code point span is only tried again when no
|
|
// strings match, and if such a non-initial span fails we stop.
|
|
if(offsets.isEmpty()) {
|
|
return pos; // No strings matched before a span.
|
|
}
|
|
// Match strings from before the next string match.
|
|
} else {
|
|
// The position is before a string match (or a single code point).
|
|
if(offsets.isEmpty()) {
|
|
// No more strings matched before a previous string match.
|
|
// Try another code point span from before the last string match.
|
|
int32_t oldPos=pos;
|
|
pos=spanSet.spanBackUTF8((const char *)s, oldPos, USET_SPAN_CONTAINED);
|
|
spanLength=oldPos-pos;
|
|
if( pos==0 || // Reached the start of the string, or
|
|
spanLength==0 // neither strings nor span progressed.
|
|
) {
|
|
return pos;
|
|
}
|
|
continue; // spanLength>0: Match strings from before a span.
|
|
} else {
|
|
// Try to match only one code point from before a string match if some
|
|
// string matched beyond it, so that we try all possible positions
|
|
// and don't overshoot.
|
|
spanLength=spanOneBackUTF8(spanSet, s, pos);
|
|
if(spanLength>0) {
|
|
if(spanLength==pos) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
// Match strings before this code point.
|
|
// There cannot be any decrements below it because UnicodeSet strings
|
|
// contain multiple code points.
|
|
pos-=spanLength;
|
|
offsets.shift(spanLength);
|
|
spanLength=0;
|
|
continue; // Match strings from before a single code point.
|
|
}
|
|
// Match strings from before the next string match.
|
|
}
|
|
}
|
|
pos-=offsets.popMinimum();
|
|
spanLength=0; // Match strings from before a string match.
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Algorithm for spanNot()==span(USET_SPAN_NOT_CONTAINED)
|
|
*
|
|
* Theoretical algorithm:
|
|
* - Iterate through the string, and at each code point boundary:
|
|
* + If the code point there is in the set, then return with the current position.
|
|
* + If a set string matches at the current position, then return with the current position.
|
|
*
|
|
* Optimized implementation:
|
|
*
|
|
* (Same assumption as for span() above.)
|
|
*
|
|
* Create and cache a spanNotSet which contains all of the single code points
|
|
* of the original set but none of its strings.
|
|
* For each set string add its initial code point to the spanNotSet.
|
|
* (Also add its final code point for spanNotBack().)
|
|
*
|
|
* - Loop:
|
|
* + Do spanLength=spanNotSet.span(USET_SPAN_NOT_CONTAINED).
|
|
* + If the current code point is in the original set, then
|
|
* return the current position.
|
|
* + If any set string matches at the current position, then
|
|
* return the current position.
|
|
* + If there is no match at the current position, neither for the code point there
|
|
* nor for any set string, then skip this code point and continue the loop.
|
|
* This happens for set-string-initial code points that were added to spanNotSet
|
|
* when there is not actually a match for such a set string.
|
|
*/
|
|
|
|
int32_t UnicodeSetStringSpan::spanNot(const UChar *s, int32_t length) const {
|
|
int32_t pos=0, rest=length;
|
|
int32_t i, stringsLength=strings.size();
|
|
do {
|
|
// Span until we find a code point from the set,
|
|
// or a code point that starts or ends some string.
|
|
i=pSpanNotSet->span(s+pos, rest, USET_SPAN_NOT_CONTAINED);
|
|
if(i==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
pos+=i;
|
|
rest-=i;
|
|
|
|
// Check whether the current code point is in the original set,
|
|
// without the string starts and ends.
|
|
int32_t cpLength=spanOne(spanSet, s+pos, rest);
|
|
if(cpLength>0) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
|
|
// Try to match the strings at pos.
|
|
for(i=0; i<stringsLength; ++i) {
|
|
if(spanLengths[i]==ALL_CP_CONTAINED) {
|
|
continue; // Irrelevant string.
|
|
}
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
if(length16<=rest && matches16CPB(s, pos, length, s16, length16)) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
}
|
|
|
|
// The span(while not contained) ended on a string start/end which is
|
|
// not in the original set. Skip this code point and continue.
|
|
// cpLength<0
|
|
pos-=cpLength;
|
|
rest+=cpLength;
|
|
} while(rest!=0);
|
|
return length; // Reached the end of the string.
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanNotBack(const UChar *s, int32_t length) const {
|
|
int32_t pos=length;
|
|
int32_t i, stringsLength=strings.size();
|
|
do {
|
|
// Span until we find a code point from the set,
|
|
// or a code point that starts or ends some string.
|
|
pos=pSpanNotSet->spanBack(s, pos, USET_SPAN_NOT_CONTAINED);
|
|
if(pos==0) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
|
|
// Check whether the current code point is in the original set,
|
|
// without the string starts and ends.
|
|
int32_t cpLength=spanOneBack(spanSet, s, pos);
|
|
if(cpLength>0) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
|
|
// Try to match the strings at pos.
|
|
for(i=0; i<stringsLength; ++i) {
|
|
// Use spanLengths rather than a spanBackLengths pointer because
|
|
// it is easier and we only need to know whether the string is irrelevant
|
|
// which is the same in either array.
|
|
if(spanLengths[i]==ALL_CP_CONTAINED) {
|
|
continue; // Irrelevant string.
|
|
}
|
|
const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i);
|
|
const UChar *s16=string.getBuffer();
|
|
int32_t length16=string.length();
|
|
if(length16<=pos && matches16CPB(s, pos-length16, length, s16, length16)) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
}
|
|
|
|
// The span(while not contained) ended on a string start/end which is
|
|
// not in the original set. Skip this code point and continue.
|
|
// cpLength<0
|
|
pos+=cpLength;
|
|
} while(pos!=0);
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanNotUTF8(const uint8_t *s, int32_t length) const {
|
|
int32_t pos=0, rest=length;
|
|
int32_t i, stringsLength=strings.size();
|
|
uint8_t *spanUTF8Lengths=spanLengths;
|
|
if(all) {
|
|
spanUTF8Lengths+=2*stringsLength;
|
|
}
|
|
do {
|
|
// Span until we find a code point from the set,
|
|
// or a code point that starts or ends some string.
|
|
i=pSpanNotSet->spanUTF8((const char *)s+pos, rest, USET_SPAN_NOT_CONTAINED);
|
|
if(i==rest) {
|
|
return length; // Reached the end of the string.
|
|
}
|
|
pos+=i;
|
|
rest-=i;
|
|
|
|
// Check whether the current code point is in the original set,
|
|
// without the string starts and ends.
|
|
int32_t cpLength=spanOneUTF8(spanSet, s+pos, rest);
|
|
if(cpLength>0) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
|
|
// Try to match the strings at pos.
|
|
const uint8_t *s8=utf8;
|
|
int32_t length8;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
// ALL_CP_CONTAINED: Irrelevant string.
|
|
if(length8!=0 && spanUTF8Lengths[i]!=ALL_CP_CONTAINED && length8<=rest && matches8(s+pos, s8, length8)) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
s8+=length8;
|
|
}
|
|
|
|
// The span(while not contained) ended on a string start/end which is
|
|
// not in the original set. Skip this code point and continue.
|
|
// cpLength<0
|
|
pos-=cpLength;
|
|
rest+=cpLength;
|
|
} while(rest!=0);
|
|
return length; // Reached the end of the string.
|
|
}
|
|
|
|
int32_t UnicodeSetStringSpan::spanNotBackUTF8(const uint8_t *s, int32_t length) const {
|
|
int32_t pos=length;
|
|
int32_t i, stringsLength=strings.size();
|
|
uint8_t *spanBackUTF8Lengths=spanLengths;
|
|
if(all) {
|
|
spanBackUTF8Lengths+=3*stringsLength;
|
|
}
|
|
do {
|
|
// Span until we find a code point from the set,
|
|
// or a code point that starts or ends some string.
|
|
pos=pSpanNotSet->spanBackUTF8((const char *)s, pos, USET_SPAN_NOT_CONTAINED);
|
|
if(pos==0) {
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
|
|
// Check whether the current code point is in the original set,
|
|
// without the string starts and ends.
|
|
int32_t cpLength=spanOneBackUTF8(spanSet, s, pos);
|
|
if(cpLength>0) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
|
|
// Try to match the strings at pos.
|
|
const uint8_t *s8=utf8;
|
|
int32_t length8;
|
|
for(i=0; i<stringsLength; ++i) {
|
|
length8=utf8Lengths[i];
|
|
// ALL_CP_CONTAINED: Irrelevant string.
|
|
if(length8!=0 && spanBackUTF8Lengths[i]!=ALL_CP_CONTAINED && length8<=pos && matches8(s+pos-length8, s8, length8)) {
|
|
return pos; // There is a set element at pos.
|
|
}
|
|
s8+=length8;
|
|
}
|
|
|
|
// The span(while not contained) ended on a string start/end which is
|
|
// not in the original set. Skip this code point and continue.
|
|
// cpLength<0
|
|
pos+=cpLength;
|
|
} while(pos!=0);
|
|
return 0; // Reached the start of the string.
|
|
}
|
|
|
|
U_NAMESPACE_END
|