|  | /* | 
|  | ****************************************************************************** | 
|  | * | 
|  | *   Copyright (C) 2016 and later: Unicode, Inc. and others. | 
|  | *   License & terms of use: http://www.unicode.org/copyright.html | 
|  | * | 
|  | ****************************************************************************** | 
|  | *   file name:  unisetspan.cpp | 
|  | *   encoding:   US-ASCII | 
|  | *   tab size:   8 (not used) | 
|  | *   indentation:4 | 
|  | * | 
|  | *   created on: 2007mar01 | 
|  | *   created by: Markus W. Scherer | 
|  | */ | 
|  |  | 
|  | #include "unicode/utypes.h" | 
|  | #include "unicode/uniset.h" | 
|  | #include "unicode/ustring.h" | 
|  | #include "unicode/utf8.h" | 
|  | #include "unicode/utf16.h" | 
|  | #include "cmemory.h" | 
|  | #include "uvector.h" | 
|  | #include "unisetspan.h" | 
|  |  | 
|  | U_NAMESPACE_BEGIN | 
|  |  | 
|  | /* | 
|  | * List of offsets from the current position from where to try matching | 
|  | * a code point or a string. | 
|  | * Store offsets rather than indexes to simplify the code and use the same list | 
|  | * for both increments (in span()) and decrements (in spanBack()). | 
|  | * | 
|  | * Assumption: The maximum offset is limited, and the offsets that are stored | 
|  | * at any one time are relatively dense, that is, there are normally no gaps of | 
|  | * hundreds or thousands of offset values. | 
|  | * | 
|  | * The implementation uses a circular buffer of byte flags, | 
|  | * each indicating whether the corresponding offset is in the list. | 
|  | * This avoids inserting into a sorted list of offsets (or absolute indexes) and | 
|  | * physically moving part of the list. | 
|  | * | 
|  | * Note: In principle, the caller should setMaxLength() to the maximum of the | 
|  | * max string length and U16_LENGTH/U8_LENGTH to account for | 
|  | * "long" single code points. | 
|  | * However, this implementation uses at least a staticList with more than | 
|  | * U8_LENGTH entries anyway. | 
|  | * | 
|  | * Note: If maxLength were guaranteed to be no more than 32 or 64, | 
|  | * the list could be stored as bit flags in a single integer. | 
|  | * Rather than handling a circular buffer with a start list index, | 
|  | * the integer would simply be shifted when lower offsets are removed. | 
|  | * UnicodeSet does not have a limit on the lengths of strings. | 
|  | */ | 
|  | class OffsetList {  // Only ever stack-allocated, does not need to inherit UMemory. | 
|  | public: | 
|  | OffsetList() : list(staticList), capacity(0), length(0), start(0) {} | 
|  |  | 
|  | ~OffsetList() { | 
|  | if(list!=staticList) { | 
|  | uprv_free(list); | 
|  | } | 
|  | } | 
|  |  | 
|  | // Call exactly once if the list is to be used. | 
|  | void setMaxLength(int32_t maxLength) { | 
|  | if(maxLength<=(int32_t)sizeof(staticList)) { | 
|  | capacity=(int32_t)sizeof(staticList); | 
|  | } else { | 
|  | UBool *l=(UBool *)uprv_malloc(maxLength); | 
|  | if(l!=NULL) { | 
|  | list=l; | 
|  | capacity=maxLength; | 
|  | } | 
|  | } | 
|  | uprv_memset(list, 0, capacity); | 
|  | } | 
|  |  | 
|  | void clear() { | 
|  | uprv_memset(list, 0, capacity); | 
|  | start=length=0; | 
|  | } | 
|  |  | 
|  | UBool isEmpty() const { | 
|  | return (UBool)(length==0); | 
|  | } | 
|  |  | 
|  | // Reduce all stored offsets by delta, used when the current position | 
|  | // moves by delta. | 
|  | // There must not be any offsets lower than delta. | 
|  | // If there is an offset equal to delta, it is removed. | 
|  | // delta=[1..maxLength] | 
|  | void shift(int32_t delta) { | 
|  | int32_t i=start+delta; | 
|  | if(i>=capacity) { | 
|  | i-=capacity; | 
|  | } | 
|  | if(list[i]) { | 
|  | list[i]=FALSE; | 
|  | --length; | 
|  | } | 
|  | start=i; | 
|  | } | 
|  |  | 
|  | // Add an offset. The list must not contain it yet. | 
|  | // offset=[1..maxLength] | 
|  | void addOffset(int32_t offset) { | 
|  | int32_t i=start+offset; | 
|  | if(i>=capacity) { | 
|  | i-=capacity; | 
|  | } | 
|  | list[i]=TRUE; | 
|  | ++length; | 
|  | } | 
|  |  | 
|  | // offset=[1..maxLength] | 
|  | UBool containsOffset(int32_t offset) const { | 
|  | int32_t i=start+offset; | 
|  | if(i>=capacity) { | 
|  | i-=capacity; | 
|  | } | 
|  | return list[i]; | 
|  | } | 
|  |  | 
|  | // Find the lowest stored offset from a non-empty list, remove it, | 
|  | // and reduce all other offsets by this minimum. | 
|  | // Returns [1..maxLength]. | 
|  | int32_t popMinimum() { | 
|  | // Look for the next offset in list[start+1..capacity-1]. | 
|  | int32_t i=start, result; | 
|  | while(++i<capacity) { | 
|  | if(list[i]) { | 
|  | list[i]=FALSE; | 
|  | --length; | 
|  | result=i-start; | 
|  | start=i; | 
|  | return result; | 
|  | } | 
|  | } | 
|  | // i==capacity | 
|  |  | 
|  | // Wrap around and look for the next offset in list[0..start]. | 
|  | // Since the list is not empty, there will be one. | 
|  | result=capacity-start; | 
|  | i=0; | 
|  | while(!list[i]) { | 
|  | ++i; | 
|  | } | 
|  | list[i]=FALSE; | 
|  | --length; | 
|  | start=i; | 
|  | return result+=i; | 
|  | } | 
|  |  | 
|  | private: | 
|  | UBool *list; | 
|  | int32_t capacity; | 
|  | int32_t length; | 
|  | int32_t start; | 
|  |  | 
|  | UBool staticList[16]; | 
|  | }; | 
|  |  | 
|  | // Get the number of UTF-8 bytes for a UTF-16 (sub)string. | 
|  | static int32_t | 
|  | getUTF8Length(const UChar *s, int32_t length) { | 
|  | UErrorCode errorCode=U_ZERO_ERROR; | 
|  | int32_t length8=0; | 
|  | u_strToUTF8(NULL, 0, &length8, s, length, &errorCode); | 
|  | if(U_SUCCESS(errorCode) || errorCode==U_BUFFER_OVERFLOW_ERROR) { | 
|  | return length8; | 
|  | } else { | 
|  | // The string contains an unpaired surrogate. | 
|  | // Ignore this string. | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | // Append the UTF-8 version of the string to t and return the appended UTF-8 length. | 
|  | static int32_t | 
|  | appendUTF8(const UChar *s, int32_t length, uint8_t *t, int32_t capacity) { | 
|  | UErrorCode errorCode=U_ZERO_ERROR; | 
|  | int32_t length8=0; | 
|  | u_strToUTF8((char *)t, capacity, &length8, s, length, &errorCode); | 
|  | if(U_SUCCESS(errorCode)) { | 
|  | return length8; | 
|  | } else { | 
|  | // The string contains an unpaired surrogate. | 
|  | // Ignore this string. | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | static inline uint8_t | 
|  | makeSpanLengthByte(int32_t spanLength) { | 
|  | // 0xfe==UnicodeSetStringSpan::LONG_SPAN | 
|  | return spanLength<0xfe ? (uint8_t)spanLength : (uint8_t)0xfe; | 
|  | } | 
|  |  | 
|  | // Construct for all variants of span(), or only for any one variant. | 
|  | // Initialize as little as possible, for single use. | 
|  | UnicodeSetStringSpan::UnicodeSetStringSpan(const UnicodeSet &set, | 
|  | const UVector &setStrings, | 
|  | uint32_t which) | 
|  | : spanSet(0, 0x10ffff), pSpanNotSet(NULL), strings(setStrings), | 
|  | utf8Lengths(NULL), spanLengths(NULL), utf8(NULL), | 
|  | utf8Length(0), | 
|  | maxLength16(0), maxLength8(0), | 
|  | all((UBool)(which==ALL)) { | 
|  | spanSet.retainAll(set); | 
|  | if(which&NOT_CONTAINED) { | 
|  | // Default to the same sets. | 
|  | // addToSpanNotSet() will create a separate set if necessary. | 
|  | pSpanNotSet=&spanSet; | 
|  | } | 
|  |  | 
|  | // Determine if the strings even need to be taken into account at all for span() etc. | 
|  | // If any string is relevant, then all strings need to be used for | 
|  | // span(longest match) but only the relevant ones for span(while contained). | 
|  | // TODO: Possible optimization: Distinguish CONTAINED vs. LONGEST_MATCH | 
|  | //   and do not store UTF-8 strings if !thisRelevant and CONTAINED. | 
|  | //   (Only store irrelevant UTF-8 strings for LONGEST_MATCH where they are relevant after all.) | 
|  | // Also count the lengths of the UTF-8 versions of the strings for memory allocation. | 
|  | int32_t stringsLength=strings.size(); | 
|  |  | 
|  | int32_t i, spanLength; | 
|  | UBool someRelevant=FALSE; | 
|  | for(i=0; i<stringsLength; ++i) { | 
|  | const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i); | 
|  | const UChar *s16=string.getBuffer(); | 
|  | int32_t length16=string.length(); | 
|  | UBool thisRelevant; | 
|  | spanLength=spanSet.span(s16, length16, USET_SPAN_CONTAINED); | 
|  | if(spanLength<length16) {  // Relevant string. | 
|  | someRelevant=thisRelevant=TRUE; | 
|  | } else { | 
|  | thisRelevant=FALSE; | 
|  | } | 
|  | if((which&UTF16) && length16>maxLength16) { | 
|  | maxLength16=length16; | 
|  | } | 
|  | if((which&UTF8) && (thisRelevant || (which&CONTAINED))) { | 
|  | int32_t length8=getUTF8Length(s16, length16); | 
|  | utf8Length+=length8; | 
|  | if(length8>maxLength8) { | 
|  | maxLength8=length8; | 
|  | } | 
|  | } | 
|  | } | 
|  | if(!someRelevant) { | 
|  | maxLength16=maxLength8=0; | 
|  | return; | 
|  | } | 
|  |  | 
|  | // Freeze after checking for the need to use strings at all because freezing | 
|  | // a set takes some time and memory which are wasted if there are no relevant strings. | 
|  | if(all) { | 
|  | spanSet.freeze(); | 
|  | } | 
|  |  | 
|  | uint8_t *spanBackLengths; | 
|  | uint8_t *spanUTF8Lengths; | 
|  | uint8_t *spanBackUTF8Lengths; | 
|  |  | 
|  | // Allocate a block of meta data. | 
|  | int32_t allocSize; | 
|  | if(all) { | 
|  | // UTF-8 lengths, 4 sets of span lengths, UTF-8 strings. | 
|  | allocSize=stringsLength*(4+1+1+1+1)+utf8Length; | 
|  | } else { | 
|  | allocSize=stringsLength;  // One set of span lengths. | 
|  | if(which&UTF8) { | 
|  | // UTF-8 lengths and UTF-8 strings. | 
|  | allocSize+=stringsLength*4+utf8Length; | 
|  | } | 
|  | } | 
|  | if(allocSize<=(int32_t)sizeof(staticLengths)) { | 
|  | utf8Lengths=staticLengths; | 
|  | } else { | 
|  | utf8Lengths=(int32_t *)uprv_malloc(allocSize); | 
|  | if(utf8Lengths==NULL) { | 
|  | maxLength16=maxLength8=0;  // Prevent usage by making needsStringSpanUTF16/8() return FALSE. | 
|  | return;  // Out of memory. | 
|  | } | 
|  | } | 
|  |  | 
|  | if(all) { | 
|  | // Store span lengths for all span() variants. | 
|  | spanLengths=(uint8_t *)(utf8Lengths+stringsLength); | 
|  | spanBackLengths=spanLengths+stringsLength; | 
|  | spanUTF8Lengths=spanBackLengths+stringsLength; | 
|  | spanBackUTF8Lengths=spanUTF8Lengths+stringsLength; | 
|  | utf8=spanBackUTF8Lengths+stringsLength; | 
|  | } else { | 
|  | // Store span lengths for only one span() variant. | 
|  | if(which&UTF8) { | 
|  | spanLengths=(uint8_t *)(utf8Lengths+stringsLength); | 
|  | utf8=spanLengths+stringsLength; | 
|  | } else { | 
|  | spanLengths=(uint8_t *)utf8Lengths; | 
|  | } | 
|  | spanBackLengths=spanUTF8Lengths=spanBackUTF8Lengths=spanLengths; | 
|  | } | 
|  |  | 
|  | // Set the meta data and pSpanNotSet and write the UTF-8 strings. | 
|  | int32_t utf8Count=0;  // Count UTF-8 bytes written so far. | 
|  |  | 
|  | for(i=0; i<stringsLength; ++i) { | 
|  | const UnicodeString &string=*(const UnicodeString *)strings.elementAt(i); | 
|  | const UChar *s16=string.getBuffer(); | 
|  | int32_t length16=string.length(); | 
|  | spanLength=spanSet.span(s16, length16, USET_SPAN_CONTAINED); | 
|  | if(spanLength<length16) {  // Relevant string. | 
|  | if(which&UTF16) { | 
|  | if(which&CONTAINED) { | 
|  | if(which&FWD) { | 
|  | spanLengths[i]=makeSpanLengthByte(spanLength); | 
|  | } | 
|  | if(which&BACK) { | 
|  | spanLength=length16-spanSet.spanBack(s16, length16, USET_SPAN_CONTAINED); | 
|  | spanBackLengths[i]=makeSpanLengthByte(spanLength); | 
|  | } | 
|  | } else /* not CONTAINED, not all, but NOT_CONTAINED */ { | 
|  | spanLengths[i]=spanBackLengths[i]=0;  // Only store a relevant/irrelevant flag. | 
|  | } | 
|  | } | 
|  | if(which&UTF8) { | 
|  | uint8_t *s8=utf8+utf8Count; | 
|  | int32_t length8=appendUTF8(s16, length16, s8, utf8Length-utf8Count); | 
|  | utf8Count+=utf8Lengths[i]=length8; | 
|  | if(length8==0) {  // Irrelevant for UTF-8 because not representable in UTF-8. | 
|  | spanUTF8Lengths[i]=spanBackUTF8Lengths[i]=(uint8_t)ALL_CP_CONTAINED; | 
|  | } else {  // Relevant for UTF-8. | 
|  | if(which&CONTAINED) { | 
|  | if(which&FWD) { | 
|  | spanLength=spanSet.spanUTF8((const char *)s8, length8, USET_SPAN_CONTAINED); | 
|  | spanUTF8Lengths[i]=makeSpanLengthByte(spanLength); | 
|  | } | 
|  | if(which&BACK) { | 
|  | spanLength=length8-spanSet.spanBackUTF8((const char *)s8, length8, USET_SPAN_CONTAINED); | 
|  | spanBackUTF8Lengths[i]=makeSpanLengthByte(spanLength); | 
|  | } | 
|  | } else /* not CONTAINED, not all, but NOT_CONTAINED */ { | 
|  | spanUTF8Lengths[i]=spanBackUTF8Lengths[i]=0;  // Only store a relevant/irrelevant flag. | 
|  | } | 
|  | } | 
|  | } | 
|  | if(which&NOT_CONTAINED) { | 
|  | // Add string start and end code points to the spanNotSet so that | 
|  | // a span(while not contained) stops before any string. | 
|  | UChar32 c; | 
|  | if(which&FWD) { | 
|  | int32_t len=0; | 
|  | U16_NEXT(s16, len, length16, c); | 
|  | addToSpanNotSet(c); | 
|  | } | 
|  | if(which&BACK) { | 
|  | int32_t len=length16; | 
|  | U16_PREV(s16, 0, len, c); | 
|  | addToSpanNotSet(c); | 
|  | } | 
|  | } | 
|  | } else {  // Irrelevant string. | 
|  | if(which&UTF8) { | 
|  | if(which&CONTAINED) {  // Only necessary for LONGEST_MATCH. | 
|  | uint8_t *s8=utf8+utf8Count; | 
|  | int32_t length8=appendUTF8(s16, length16, s8, utf8Length-utf8Count); | 
|  | utf8Count+=utf8Lengths[i]=length8; | 
|  | } else { | 
|  | utf8Lengths[i]=0; | 
|  | } | 
|  | } | 
|  | if(all) { | 
|  | spanLengths[i]=spanBackLengths[i]= | 
|  | spanUTF8Lengths[i]=spanBackUTF8Lengths[i]= | 
|  | (uint8_t)ALL_CP_CONTAINED; | 
|  | } else { | 
|  | // All spanXYZLengths pointers contain the same address. | 
|  | spanLengths[i]=(uint8_t)ALL_CP_CONTAINED; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | // Finish. | 
|  | if(all) { | 
|  | pSpanNotSet->freeze(); | 
|  | } | 
|  | } | 
|  |  | 
|  | // Copy constructor. Assumes which==ALL for a frozen set. | 
|  | UnicodeSetStringSpan::UnicodeSetStringSpan(const UnicodeSetStringSpan &otherStringSpan, | 
|  | const UVector &newParentSetStrings) | 
|  | : spanSet(otherStringSpan.spanSet), pSpanNotSet(NULL), strings(newParentSetStrings), | 
|  | utf8Lengths(NULL), spanLengths(NULL), utf8(NULL), | 
|  | utf8Length(otherStringSpan.utf8Length), | 
|  | maxLength16(otherStringSpan.maxLength16), maxLength8(otherStringSpan.maxLength8), | 
|  | all(TRUE) { | 
|  | if(otherStringSpan.pSpanNotSet==&otherStringSpan.spanSet) { | 
|  | pSpanNotSet=&spanSet; | 
|  | } else { | 
|  | pSpanNotSet=(UnicodeSet *)otherStringSpan.pSpanNotSet->clone(); | 
|  | } | 
|  |  | 
|  | // Allocate a block of meta data. | 
|  | // UTF-8 lengths, 4 sets of span lengths, UTF-8 strings. | 
|  | int32_t stringsLength=strings.size(); | 
|  | int32_t allocSize=stringsLength*(4+1+1+1+1)+utf8Length; | 
|  | if(allocSize<=(int32_t)sizeof(staticLengths)) { | 
|  | utf8Lengths=staticLengths; | 
|  | } else { | 
|  | utf8Lengths=(int32_t *)uprv_malloc(allocSize); | 
|  | if(utf8Lengths==NULL) { | 
|  | maxLength16=maxLength8=0;  // Prevent usage by making needsStringSpanUTF16/8() return FALSE. | 
|  | return;  // Out of memory. | 
|  | } | 
|  | } | 
|  |  | 
|  | spanLengths=(uint8_t *)(utf8Lengths+stringsLength); | 
|  | utf8=spanLengths+stringsLength*4; | 
|  | uprv_memcpy(utf8Lengths, otherStringSpan.utf8Lengths, allocSize); | 
|  | } | 
|  |  | 
|  | UnicodeSetStringSpan::~UnicodeSetStringSpan() { | 
|  | if(pSpanNotSet!=NULL && pSpanNotSet!=&spanSet) { | 
|  | delete pSpanNotSet; | 
|  | } | 
|  | if(utf8Lengths!=NULL && utf8Lengths!=staticLengths) { | 
|  | uprv_free(utf8Lengths); | 
|  | } | 
|  | } | 
|  |  | 
|  | void UnicodeSetStringSpan::addToSpanNotSet(UChar32 c) { | 
|  | if(pSpanNotSet==NULL || pSpanNotSet==&spanSet) { | 
|  | if(spanSet.contains(c)) { | 
|  | return;  // Nothing to do. | 
|  | } | 
|  | UnicodeSet *newSet=(UnicodeSet *)spanSet.cloneAsThawed(); | 
|  | if(newSet==NULL) { | 
|  | return;  // Out of memory. | 
|  | } else { | 
|  | pSpanNotSet=newSet; | 
|  | } | 
|  | } | 
|  | pSpanNotSet->add(c); | 
|  | } | 
|  |  | 
|  | // Compare strings without any argument checks. Requires length>0. | 
|  | static inline UBool | 
|  | matches16(const UChar *s, const UChar *t, int32_t length) { | 
|  | do { | 
|  | if(*s++!=*t++) { | 
|  | return FALSE; | 
|  | } | 
|  | } while(--length>0); | 
|  | return TRUE; | 
|  | } | 
|  |  | 
|  | static inline UBool | 
|  | matches8(const uint8_t *s, const uint8_t *t, int32_t length) { | 
|  | do { | 
|  | if(*s++!=*t++) { | 
|  | return FALSE; | 
|  | } | 
|  | } while(--length>0); | 
|  | return TRUE; | 
|  | } | 
|  |  | 
|  | // Compare 16-bit Unicode strings (which may be malformed UTF-16) | 
|  | // at code point boundaries. | 
|  | // That is, each edge of a match must not be in the middle of a surrogate pair. | 
|  | static inline UBool | 
|  | matches16CPB(const UChar *s, int32_t start, int32_t limit, const UChar *t, int32_t length) { | 
|  | s+=start; | 
|  | limit-=start; | 
|  | return matches16(s, t, length) && | 
|  | !(0<start && U16_IS_LEAD(s[-1]) && U16_IS_TRAIL(s[0])) && | 
|  | !(length<limit && U16_IS_LEAD(s[length-1]) && U16_IS_TRAIL(s[length])); | 
|  | } | 
|  |  | 
|  | // Does the set contain the next code point? | 
|  | // If so, return its length; otherwise return its negative length. | 
|  | static inline int32_t | 
|  | spanOne(const UnicodeSet &set, const UChar *s, int32_t length) { | 
|  | 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((int8_t)c>=0) { | 
|  | 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((int8_t)c>=0) { | 
|  | 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 |