The Tor Browser: intl/icu/source/common/dictbe.cpp@6474c204b198 (annotated)

intl/icu/source/common/dictbe.cpp@6474c204b198 (annotated)

intl/icu/source/common/dictbe.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /**
  *******************************************************************************
  * Copyright (C) 2006-2013, International Business Machines Corporation
  * and others. All Rights Reserved.
  *******************************************************************************
  */
 #include "unicode/utypes.h"
 #if !UCONFIG_NO_BREAK_ITERATION
 #include "brkeng.h"
 #include "dictbe.h"
 #include "unicode/uniset.h"
 #include "unicode/chariter.h"
 #include "unicode/ubrk.h"
 #include "uvector.h"
 #include "uassert.h"
 #include "unicode/normlzr.h"
 #include "cmemory.h"
 #include "dictionarydata.h"
 U_NAMESPACE_BEGIN
 /*
  ******************************************************************
  */
 DictionaryBreakEngine::DictionaryBreakEngine(uint32_t breakTypes) {
     fTypes = breakTypes;
 }
 DictionaryBreakEngine::~DictionaryBreakEngine() {
 }
 UBool
 DictionaryBreakEngine::handles(UChar32 c, int32_t breakType) const {
     return (breakType >= 0 && breakType < 32 && (((uint32_t)1 << breakType) & fTypes)
             && fSet.contains(c));
 }
 int32_t
 DictionaryBreakEngine::findBreaks( UText *text,
                                  int32_t startPos,
                                  int32_t endPos,
                                  UBool reverse,
                                  int32_t breakType,
                                  UStack &foundBreaks ) const {
     int32_t result = 0;
     // Find the span of characters included in the set.
     int32_t start = (int32_t)utext_getNativeIndex(text);
     int32_t current;
     int32_t rangeStart;
     int32_t rangeEnd;
     UChar32 c = utext_current32(text);
     if (reverse) {
         UBool   isDict = fSet.contains(c);
         while((current = (int32_t)utext_getNativeIndex(text)) > startPos && isDict) {
             c = utext_previous32(text);
             isDict = fSet.contains(c);
         }
         rangeStart = (current < startPos) ? startPos : current+(isDict ? 0 : 1);
         rangeEnd = start + 1;
     }
     else {
         while((current = (int32_t)utext_getNativeIndex(text)) < endPos && fSet.contains(c)) {
             utext_next32(text);         // TODO:  recast loop for postincrement
             c = utext_current32(text);
         }
         rangeStart = start;
         rangeEnd = current;
     }
     if (breakType >= 0 && breakType < 32 && (((uint32_t)1 << breakType) & fTypes)) {
         result = divideUpDictionaryRange(text, rangeStart, rangeEnd, foundBreaks);
         utext_setNativeIndex(text, current);
     }
     return result;
 }
 void
 DictionaryBreakEngine::setCharacters( const UnicodeSet &set ) {
     fSet = set;
     // Compact for caching
     fSet.compact();
 }
 /*
  ******************************************************************
  * PossibleWord
  */
 // Helper class for improving readability of the Thai/Lao/Khmer word break
 // algorithm. The implementation is completely inline.
 // List size, limited by the maximum number of words in the dictionary
 // that form a nested sequence.
 #define POSSIBLE_WORD_LIST_MAX 20
 class PossibleWord {
 private:
     // list of word candidate lengths, in increasing length order
     int32_t   lengths[POSSIBLE_WORD_LIST_MAX];
     int32_t   count;      // Count of candidates
     int32_t   prefix;     // The longest match with a dictionary word
     int32_t   offset;     // Offset in the text of these candidates
     int       mark;       // The preferred candidate's offset
     int       current;    // The candidate we're currently looking at
 public:
     PossibleWord();
     ~PossibleWord();
     // Fill the list of candidates if needed, select the longest, and return the number found
     int       candidates( UText *text, DictionaryMatcher *dict, int32_t rangeEnd );
     // Select the currently marked candidate, point after it in the text, and invalidate self
     int32_t   acceptMarked( UText *text );
     // Back up from the current candidate to the next shorter one; return TRUE if that exists
     // and point the text after it
     UBool     backUp( UText *text );
     // Return the longest prefix this candidate location shares with a dictionary word
     int32_t   longestPrefix();
     // Mark the current candidate as the one we like
     void      markCurrent();
 };
 inline
 PossibleWord::PossibleWord() {
     offset = -1;
 }
 inline
 PossibleWord::~PossibleWord() {
 }
 inline int
 PossibleWord::candidates( UText *text, DictionaryMatcher *dict, int32_t rangeEnd ) {
     // TODO: If getIndex is too slow, use offset < 0 and add discardAll()
     int32_t start = (int32_t)utext_getNativeIndex(text);
     if (start != offset) {
         offset = start;
         prefix = dict->matches(text, rangeEnd-start, lengths, count, sizeof(lengths)/sizeof(lengths[0]));
         // Dictionary leaves text after longest prefix, not longest word. Back up.
         if (count <= 0) {
             utext_setNativeIndex(text, start);
         }
     }
     if (count > 0) {
         utext_setNativeIndex(text, start+lengths[count-1]);
     }
     current = count-1;
     mark = current;
     return count;
 }
 inline int32_t
 PossibleWord::acceptMarked( UText *text ) {
     utext_setNativeIndex(text, offset + lengths[mark]);
     return lengths[mark];
 }
 inline UBool
 PossibleWord::backUp( UText *text ) {
     if (current > 0) {
         utext_setNativeIndex(text, offset + lengths[--current]);
         return TRUE;
     }
     return FALSE;
 }
 inline int32_t
 PossibleWord::longestPrefix() {
     return prefix;
 }
 inline void
 PossibleWord::markCurrent() {
     mark = current;
 }
 /*
  ******************************************************************
  * ThaiBreakEngine
  */
 // How many words in a row are "good enough"?
 #define THAI_LOOKAHEAD 3
 // Will not combine a non-word with a preceding dictionary word longer than this
 #define THAI_ROOT_COMBINE_THRESHOLD 3
 // Will not combine a non-word that shares at least this much prefix with a
 // dictionary word, with a preceding word
 #define THAI_PREFIX_COMBINE_THRESHOLD 3
 // Ellision character
 #define THAI_PAIYANNOI 0x0E2F
 // Repeat character
 #define THAI_MAIYAMOK 0x0E46
 // Minimum word size
 #define THAI_MIN_WORD 2
 // Minimum number of characters for two words
 #define THAI_MIN_WORD_SPAN (THAI_MIN_WORD * 2)
 ThaiBreakEngine::ThaiBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
     : DictionaryBreakEngine((1<<UBRK_WORD) | (1<<UBRK_LINE)),
       fDictionary(adoptDictionary)
 {
     fThaiWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Thai:]&[:LineBreak=SA:]]"), status);
     if (U_SUCCESS(status)) {
         setCharacters(fThaiWordSet);
     }
     fMarkSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Thai:]&[:LineBreak=SA:]&[:M:]]"), status);
     fMarkSet.add(0x0020);
     fEndWordSet = fThaiWordSet;
     fEndWordSet.remove(0x0E31);             // MAI HAN-AKAT
     fEndWordSet.remove(0x0E40, 0x0E44);     // SARA E through SARA AI MAIMALAI
     fBeginWordSet.add(0x0E01, 0x0E2E);      // KO KAI through HO NOKHUK
     fBeginWordSet.add(0x0E40, 0x0E44);      // SARA E through SARA AI MAIMALAI
     fSuffixSet.add(THAI_PAIYANNOI);
     fSuffixSet.add(THAI_MAIYAMOK);
     // Compact for caching.
     fMarkSet.compact();
     fEndWordSet.compact();
     fBeginWordSet.compact();
     fSuffixSet.compact();
 }
 ThaiBreakEngine::~ThaiBreakEngine() {
     delete fDictionary;
 }
 int32_t
 ThaiBreakEngine::divideUpDictionaryRange( UText *text,
                                                 int32_t rangeStart,
                                                 int32_t rangeEnd,
                                                 UStack &foundBreaks ) const {
     if ((rangeEnd - rangeStart) < THAI_MIN_WORD_SPAN) {
         return 0;       // Not enough characters for two words
     }
     uint32_t wordsFound = 0;
     int32_t wordLength;
     int32_t current;
     UErrorCode status = U_ZERO_ERROR;
     PossibleWord words[THAI_LOOKAHEAD];
     UChar32 uc;
     utext_setNativeIndex(text, rangeStart);
     while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
         wordLength = 0;
         // Look for candidate words at the current position
         int candidates = words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
         // If we found exactly one, use that
         if (candidates == 1) {
             wordLength = words[wordsFound % THAI_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // If there was more than one, see which one can take us forward the most words
         else if (candidates > 1) {
             // If we're already at the end of the range, we're done
             if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                 goto foundBest;
             }
             do {
                 int wordsMatched = 1;
                 if (words[(wordsFound + 1) % THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) > 0) {
                     if (wordsMatched < 2) {
                         // Followed by another dictionary word; mark first word as a good candidate
                         words[wordsFound%THAI_LOOKAHEAD].markCurrent();
                         wordsMatched = 2;
                     }
                     // If we're already at the end of the range, we're done
                     if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                         goto foundBest;
                     }
                     // See if any of the possible second words is followed by a third word
                     do {
                         // If we find a third word, stop right away
                         if (words[(wordsFound + 2) % THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd)) {
                             words[wordsFound % THAI_LOOKAHEAD].markCurrent();
                             goto foundBest;
                         }
                     }
                     while (words[(wordsFound + 1) % THAI_LOOKAHEAD].backUp(text));
                 }
             }
             while (words[wordsFound % THAI_LOOKAHEAD].backUp(text));
 foundBest:
             wordLength = words[wordsFound % THAI_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // We come here after having either found a word or not. We look ahead to the
         // next word. If it's not a dictionary word, we will combine it withe the word we
         // just found (if there is one), but only if the preceding word does not exceed
         // the threshold.
         // The text iterator should now be positioned at the end of the word we found.
         if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength < THAI_ROOT_COMBINE_THRESHOLD) {
             // if it is a dictionary word, do nothing. If it isn't, then if there is
             // no preceding word, or the non-word shares less than the minimum threshold
             // of characters with a dictionary word, then scan to resynchronize
             if (words[wordsFound % THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
                   && (wordLength == 0
                       || words[wordsFound%THAI_LOOKAHEAD].longestPrefix() < THAI_PREFIX_COMBINE_THRESHOLD)) {
                 // Look for a plausible word boundary
                 //TODO: This section will need a rework for UText.
                 int32_t remaining = rangeEnd - (current+wordLength);
                 UChar32 pc = utext_current32(text);
                 int32_t chars = 0;
                 for (;;) {
                     utext_next32(text);
                     uc = utext_current32(text);
                     // TODO: Here we're counting on the fact that the SA languages are all
                     // in the BMP. This should get fixed with the UText rework.
                     chars += 1;
                     if (--remaining <= 0) {
                         break;
                     }
                     if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
                         // Maybe. See if it's in the dictionary.
                         // NOTE: In the original Apple code, checked that the next
                         // two characters after uc were not 0x0E4C THANTHAKHAT before
                         // checking the dictionary. That is just a performance filter,
                         // but it's not clear it's faster than checking the trie.
                         int candidates = words[(wordsFound + 1) % THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
                         utext_setNativeIndex(text, current + wordLength + chars);
                         if (candidates > 0) {
                             break;
                         }
                     }
                     pc = uc;
                 }
                 // Bump the word count if there wasn't already one
                 if (wordLength <= 0) {
                     wordsFound += 1;
                 }
                 // Update the length with the passed-over characters
                 wordLength += chars;
             }
             else {
                 // Back up to where we were for next iteration
                 utext_setNativeIndex(text, current+wordLength);
             }
         }
         // Never stop before a combining mark.
         int32_t currPos;
         while ((currPos = (int32_t)utext_getNativeIndex(text)) < rangeEnd && fMarkSet.contains(utext_current32(text))) {
             utext_next32(text);
             wordLength += (int32_t)utext_getNativeIndex(text) - currPos;
         }
         // Look ahead for possible suffixes if a dictionary word does not follow.
         // We do this in code rather than using a rule so that the heuristic
         // resynch continues to function. For example, one of the suffix characters
         // could be a typo in the middle of a word.
         if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength > 0) {
             if (words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
                 && fSuffixSet.contains(uc = utext_current32(text))) {
                 if (uc == THAI_PAIYANNOI) {
                     if (!fSuffixSet.contains(utext_previous32(text))) {
                         // Skip over previous end and PAIYANNOI
                         utext_next32(text);
                         utext_next32(text);
                         wordLength += 1;            // Add PAIYANNOI to word
                         uc = utext_current32(text);     // Fetch next character
                     }
                     else {
                         // Restore prior position
                         utext_next32(text);
                     }
                 }
                 if (uc == THAI_MAIYAMOK) {
                     if (utext_previous32(text) != THAI_MAIYAMOK) {
                         // Skip over previous end and MAIYAMOK
                         utext_next32(text);
                         utext_next32(text);
                         wordLength += 1;            // Add MAIYAMOK to word
                     }
                     else {
                         // Restore prior position
                         utext_next32(text);
                     }
                 }
             }
             else {
                 utext_setNativeIndex(text, current+wordLength);
             }
         }
         // Did we find a word on this iteration? If so, push it on the break stack
         if (wordLength > 0) {
             foundBreaks.push((current+wordLength), status);
         }
     }
     // Don't return a break for the end of the dictionary range if there is one there.
     if (foundBreaks.peeki() >= rangeEnd) {
         (void) foundBreaks.popi();
         wordsFound -= 1;
     }
     return wordsFound;
 }
 /*
  ******************************************************************
  * LaoBreakEngine
  */
 // How many words in a row are "good enough"?
 #define LAO_LOOKAHEAD 3
 // Will not combine a non-word with a preceding dictionary word longer than this
 #define LAO_ROOT_COMBINE_THRESHOLD 3
 // Will not combine a non-word that shares at least this much prefix with a
 // dictionary word, with a preceding word
 #define LAO_PREFIX_COMBINE_THRESHOLD 3
 // Minimum word size
 #define LAO_MIN_WORD 2
 // Minimum number of characters for two words
 #define LAO_MIN_WORD_SPAN (LAO_MIN_WORD * 2)
 LaoBreakEngine::LaoBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
     : DictionaryBreakEngine((1<<UBRK_WORD) | (1<<UBRK_LINE)),
       fDictionary(adoptDictionary)
 {
     fLaoWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Laoo:]&[:LineBreak=SA:]]"), status);
     if (U_SUCCESS(status)) {
         setCharacters(fLaoWordSet);
     }
     fMarkSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Laoo:]&[:LineBreak=SA:]&[:M:]]"), status);
     fMarkSet.add(0x0020);
     fEndWordSet = fLaoWordSet;
     fEndWordSet.remove(0x0EC0, 0x0EC4);     // prefix vowels
     fBeginWordSet.add(0x0E81, 0x0EAE);      // basic consonants (including holes for corresponding Thai characters)
     fBeginWordSet.add(0x0EDC, 0x0EDD);      // digraph consonants (no Thai equivalent)
     fBeginWordSet.add(0x0EC0, 0x0EC4);      // prefix vowels
     // Compact for caching.
     fMarkSet.compact();
     fEndWordSet.compact();
     fBeginWordSet.compact();
 }
 LaoBreakEngine::~LaoBreakEngine() {
     delete fDictionary;
 }
 int32_t
 LaoBreakEngine::divideUpDictionaryRange( UText *text,
                                                 int32_t rangeStart,
                                                 int32_t rangeEnd,
                                                 UStack &foundBreaks ) const {
     if ((rangeEnd - rangeStart) < LAO_MIN_WORD_SPAN) {
         return 0;       // Not enough characters for two words
     }
     uint32_t wordsFound = 0;
     int32_t wordLength;
     int32_t current;
     UErrorCode status = U_ZERO_ERROR;
     PossibleWord words[LAO_LOOKAHEAD];
     UChar32 uc;
     utext_setNativeIndex(text, rangeStart);
     while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
         wordLength = 0;
         // Look for candidate words at the current position
         int candidates = words[wordsFound%LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
         // If we found exactly one, use that
         if (candidates == 1) {
             wordLength = words[wordsFound % LAO_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // If there was more than one, see which one can take us forward the most words
         else if (candidates > 1) {
             // If we're already at the end of the range, we're done
             if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                 goto foundBest;
             }
             do {
                 int wordsMatched = 1;
                 if (words[(wordsFound + 1) % LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) > 0) {
                     if (wordsMatched < 2) {
                         // Followed by another dictionary word; mark first word as a good candidate
                         words[wordsFound%LAO_LOOKAHEAD].markCurrent();
                         wordsMatched = 2;
                     }
                     // If we're already at the end of the range, we're done
                     if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                         goto foundBest;
                     }
                     // See if any of the possible second words is followed by a third word
                     do {
                         // If we find a third word, stop right away
                         if (words[(wordsFound + 2) % LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd)) {
                             words[wordsFound % LAO_LOOKAHEAD].markCurrent();
                             goto foundBest;
                         }
                     }
                     while (words[(wordsFound + 1) % LAO_LOOKAHEAD].backUp(text));
                 }
             }
             while (words[wordsFound % LAO_LOOKAHEAD].backUp(text));
 foundBest:
             wordLength = words[wordsFound % LAO_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // We come here after having either found a word or not. We look ahead to the
         // next word. If it's not a dictionary word, we will combine it withe the word we
         // just found (if there is one), but only if the preceding word does not exceed
         // the threshold.
         // The text iterator should now be positioned at the end of the word we found.
         if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength < LAO_ROOT_COMBINE_THRESHOLD) {
             // if it is a dictionary word, do nothing. If it isn't, then if there is
             // no preceding word, or the non-word shares less than the minimum threshold
             // of characters with a dictionary word, then scan to resynchronize
             if (words[wordsFound % LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
                   && (wordLength == 0
                       || words[wordsFound%LAO_LOOKAHEAD].longestPrefix() < LAO_PREFIX_COMBINE_THRESHOLD)) {
                 // Look for a plausible word boundary
                 //TODO: This section will need a rework for UText.
                 int32_t remaining = rangeEnd - (current+wordLength);
                 UChar32 pc = utext_current32(text);
                 int32_t chars = 0;
                 for (;;) {
                     utext_next32(text);
                     uc = utext_current32(text);
                     // TODO: Here we're counting on the fact that the SA languages are all
                     // in the BMP. This should get fixed with the UText rework.
                     chars += 1;
                     if (--remaining <= 0) {
                         break;
                     }
                     if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
                         // Maybe. See if it's in the dictionary.
                         int candidates = words[(wordsFound + 1) % LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
                         utext_setNativeIndex(text, current + wordLength + chars);
                         if (candidates > 0) {
                             break;
                         }
                     }
                     pc = uc;
                 }
                 // Bump the word count if there wasn't already one
                 if (wordLength <= 0) {
                     wordsFound += 1;
                 }
                 // Update the length with the passed-over characters
                 wordLength += chars;
             }
             else {
                 // Back up to where we were for next iteration
                 utext_setNativeIndex(text, current+wordLength);
             }
         }
         // Never stop before a combining mark.
         int32_t currPos;
         while ((currPos = (int32_t)utext_getNativeIndex(text)) < rangeEnd && fMarkSet.contains(utext_current32(text))) {
             utext_next32(text);
             wordLength += (int32_t)utext_getNativeIndex(text) - currPos;
         }
         // Look ahead for possible suffixes if a dictionary word does not follow.
         // We do this in code rather than using a rule so that the heuristic
         // resynch continues to function. For example, one of the suffix characters
         // could be a typo in the middle of a word.
         // NOT CURRENTLY APPLICABLE TO LAO
         // Did we find a word on this iteration? If so, push it on the break stack
         if (wordLength > 0) {
             foundBreaks.push((current+wordLength), status);
         }
     }
     // Don't return a break for the end of the dictionary range if there is one there.
     if (foundBreaks.peeki() >= rangeEnd) {
         (void) foundBreaks.popi();
         wordsFound -= 1;
     }
     return wordsFound;
 }
 /*
  ******************************************************************
  * KhmerBreakEngine
  */
 // How many words in a row are "good enough"?
 #define KHMER_LOOKAHEAD 3
 // Will not combine a non-word with a preceding dictionary word longer than this
 #define KHMER_ROOT_COMBINE_THRESHOLD 3
 // Will not combine a non-word that shares at least this much prefix with a
 // dictionary word, with a preceding word
 #define KHMER_PREFIX_COMBINE_THRESHOLD 3
 // Minimum word size
 #define KHMER_MIN_WORD 2
 // Minimum number of characters for two words
 #define KHMER_MIN_WORD_SPAN (KHMER_MIN_WORD * 2)
 KhmerBreakEngine::KhmerBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
     : DictionaryBreakEngine((1 << UBRK_WORD) | (1 << UBRK_LINE)),
       fDictionary(adoptDictionary)
 {
     fKhmerWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Khmr:]&[:LineBreak=SA:]]"), status);
     if (U_SUCCESS(status)) {
         setCharacters(fKhmerWordSet);
     }
     fMarkSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Khmr:]&[:LineBreak=SA:]&[:M:]]"), status);
     fMarkSet.add(0x0020);
     fEndWordSet = fKhmerWordSet;
     fBeginWordSet.add(0x1780, 0x17B3);
     //fBeginWordSet.add(0x17A3, 0x17A4);      // deprecated vowels
     //fEndWordSet.remove(0x17A5, 0x17A9);     // Khmer independent vowels that can't end a word
     //fEndWordSet.remove(0x17B2);             // Khmer independent vowel that can't end a word
     fEndWordSet.remove(0x17D2);             // KHMER SIGN COENG that combines some following characters
     //fEndWordSet.remove(0x17B6, 0x17C5);     // Remove dependent vowels
 //    fEndWordSet.remove(0x0E31);             // MAI HAN-AKAT
 //    fEndWordSet.remove(0x0E40, 0x0E44);     // SARA E through SARA AI MAIMALAI
 //    fBeginWordSet.add(0x0E01, 0x0E2E);      // KO KAI through HO NOKHUK
 //    fBeginWordSet.add(0x0E40, 0x0E44);      // SARA E through SARA AI MAIMALAI
 //    fSuffixSet.add(THAI_PAIYANNOI);
 //    fSuffixSet.add(THAI_MAIYAMOK);
     // Compact for caching.
     fMarkSet.compact();
     fEndWordSet.compact();
     fBeginWordSet.compact();
 //    fSuffixSet.compact();
 }
 KhmerBreakEngine::~KhmerBreakEngine() {
     delete fDictionary;
 }
 int32_t
 KhmerBreakEngine::divideUpDictionaryRange( UText *text,
                                                 int32_t rangeStart,
                                                 int32_t rangeEnd,
                                                 UStack &foundBreaks ) const {
     if ((rangeEnd - rangeStart) < KHMER_MIN_WORD_SPAN) {
         return 0;       // Not enough characters for two words
     }
     uint32_t wordsFound = 0;
     int32_t wordLength;
     int32_t current;
     UErrorCode status = U_ZERO_ERROR;
     PossibleWord words[KHMER_LOOKAHEAD];
     UChar32 uc;
     utext_setNativeIndex(text, rangeStart);
     while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
         wordLength = 0;
         // Look for candidate words at the current position
         int candidates = words[wordsFound%KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
         // If we found exactly one, use that
         if (candidates == 1) {
             wordLength = words[wordsFound%KHMER_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // If there was more than one, see which one can take us forward the most words
         else if (candidates > 1) {
             // If we're already at the end of the range, we're done
             if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                 goto foundBest;
             }
             do {
                 int wordsMatched = 1;
                 if (words[(wordsFound + 1) % KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) > 0) {
                     if (wordsMatched < 2) {
                         // Followed by another dictionary word; mark first word as a good candidate
                         words[wordsFound % KHMER_LOOKAHEAD].markCurrent();
                         wordsMatched = 2;
                     }
                     // If we're already at the end of the range, we're done
                     if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) {
                         goto foundBest;
                     }
                     // See if any of the possible second words is followed by a third word
                     do {
                         // If we find a third word, stop right away
                         if (words[(wordsFound + 2) % KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd)) {
                             words[wordsFound % KHMER_LOOKAHEAD].markCurrent();
                             goto foundBest;
                         }
                     }
                     while (words[(wordsFound + 1) % KHMER_LOOKAHEAD].backUp(text));
                 }
             }
             while (words[wordsFound % KHMER_LOOKAHEAD].backUp(text));
 foundBest:
             wordLength = words[wordsFound % KHMER_LOOKAHEAD].acceptMarked(text);
             wordsFound += 1;
         }
         // We come here after having either found a word or not. We look ahead to the
         // next word. If it's not a dictionary word, we will combine it with the word we
         // just found (if there is one), but only if the preceding word does not exceed
         // the threshold.
         // The text iterator should now be positioned at the end of the word we found.
         if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength < KHMER_ROOT_COMBINE_THRESHOLD) {
             // if it is a dictionary word, do nothing. If it isn't, then if there is
             // no preceding word, or the non-word shares less than the minimum threshold
             // of characters with a dictionary word, then scan to resynchronize
             if (words[wordsFound % KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
                   && (wordLength == 0
                       || words[wordsFound % KHMER_LOOKAHEAD].longestPrefix() < KHMER_PREFIX_COMBINE_THRESHOLD)) {
                 // Look for a plausible word boundary
                 //TODO: This section will need a rework for UText.
                 int32_t remaining = rangeEnd - (current+wordLength);
                 UChar32 pc = utext_current32(text);
                 int32_t chars = 0;
                 for (;;) {
                     utext_next32(text);
                     uc = utext_current32(text);
                     // TODO: Here we're counting on the fact that the SA languages are all
                     // in the BMP. This should get fixed with the UText rework.
                     chars += 1;
                     if (--remaining <= 0) {
                         break;
                     }
                     if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
                         // Maybe. See if it's in the dictionary.
                         int candidates = words[(wordsFound + 1) % KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
                         utext_setNativeIndex(text, current+wordLength+chars);
                         if (candidates > 0) {
                             break;
                         }
                     }
                     pc = uc;
                 }
                 // Bump the word count if there wasn't already one
                 if (wordLength <= 0) {
                     wordsFound += 1;
                 }
                 // Update the length with the passed-over characters
                 wordLength += chars;
             }
             else {
                 // Back up to where we were for next iteration
                 utext_setNativeIndex(text, current+wordLength);
             }
         }
         // Never stop before a combining mark.
         int32_t currPos;
         while ((currPos = (int32_t)utext_getNativeIndex(text)) < rangeEnd && fMarkSet.contains(utext_current32(text))) {
             utext_next32(text);
             wordLength += (int32_t)utext_getNativeIndex(text) - currPos;
         }
         // Look ahead for possible suffixes if a dictionary word does not follow.
         // We do this in code rather than using a rule so that the heuristic
         // resynch continues to function. For example, one of the suffix characters
         // could be a typo in the middle of a word.
 //        if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength > 0) {
 //            if (words[wordsFound%KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
 //                && fSuffixSet.contains(uc = utext_current32(text))) {
 //                if (uc == KHMER_PAIYANNOI) {
 //                    if (!fSuffixSet.contains(utext_previous32(text))) {
 //                        // Skip over previous end and PAIYANNOI
 //                        utext_next32(text);
 //                        utext_next32(text);
 //                        wordLength += 1;            // Add PAIYANNOI to word
 //                        uc = utext_current32(text);     // Fetch next character
 //                    }
 //                    else {
 //                        // Restore prior position
 //                        utext_next32(text);
 //                    }
 //                }
 //                if (uc == KHMER_MAIYAMOK) {
 //                    if (utext_previous32(text) != KHMER_MAIYAMOK) {
 //                        // Skip over previous end and MAIYAMOK
 //                        utext_next32(text);
 //                        utext_next32(text);
 //                        wordLength += 1;            // Add MAIYAMOK to word
 //                    }
 //                    else {
 //                        // Restore prior position
 //                        utext_next32(text);
 //                    }
 //                }
 //            }
 //            else {
 //                utext_setNativeIndex(text, current+wordLength);
 //            }
 //        }
         // Did we find a word on this iteration? If so, push it on the break stack
         if (wordLength > 0) {
             foundBreaks.push((current+wordLength), status);
         }
     }
     // Don't return a break for the end of the dictionary range if there is one there.
     if (foundBreaks.peeki() >= rangeEnd) {
         (void) foundBreaks.popi();
         wordsFound -= 1;
     }
     return wordsFound;
 }
 #if !UCONFIG_NO_NORMALIZATION
 /*
  ******************************************************************
  * CjkBreakEngine
  */
 static const uint32_t kuint32max = 0xFFFFFFFF;
 CjkBreakEngine::CjkBreakEngine(DictionaryMatcher *adoptDictionary, LanguageType type, UErrorCode &status)
 : DictionaryBreakEngine(1 << UBRK_WORD), fDictionary(adoptDictionary) {
     // Korean dictionary only includes Hangul syllables
     fHangulWordSet.applyPattern(UNICODE_STRING_SIMPLE("[\\uac00-\\ud7a3]"), status);
     fHanWordSet.applyPattern(UNICODE_STRING_SIMPLE("[:Han:]"), status);
     fKatakanaWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Katakana:]\\uff9e\\uff9f]"), status);
     fHiraganaWordSet.applyPattern(UNICODE_STRING_SIMPLE("[:Hiragana:]"), status);
     if (U_SUCCESS(status)) {
         // handle Korean and Japanese/Chinese using different dictionaries
         if (type == kKorean) {
             setCharacters(fHangulWordSet);
         } else { //Chinese and Japanese
             UnicodeSet cjSet;
             cjSet.addAll(fHanWordSet);
             cjSet.addAll(fKatakanaWordSet);
             cjSet.addAll(fHiraganaWordSet);
             cjSet.add(0xFF70); // HALFWIDTH KATAKANA-HIRAGANA PROLONGED SOUND MARK
             cjSet.add(0x30FC); // KATAKANA-HIRAGANA PROLONGED SOUND MARK
             setCharacters(cjSet);
         }
     }
 }
 CjkBreakEngine::~CjkBreakEngine(){
     delete fDictionary;
 }
 // The katakanaCost values below are based on the length frequencies of all
 // katakana phrases in the dictionary
 static const int kMaxKatakanaLength = 8;
 static const int kMaxKatakanaGroupLength = 20;
 static const uint32_t maxSnlp = 255;
 static inline uint32_t getKatakanaCost(int wordLength){
     //TODO: fill array with actual values from dictionary!
     static const uint32_t katakanaCost[kMaxKatakanaLength + 1]
                                        = {8192, 984, 408, 240, 204, 252, 300, 372, 480};
     return (wordLength > kMaxKatakanaLength) ? 8192 : katakanaCost[wordLength];
 }
 static inline bool isKatakana(uint16_t value) {
     return (value >= 0x30A1u && value <= 0x30FEu && value != 0x30FBu) ||
             (value >= 0xFF66u && value <= 0xFF9fu);
 }
 // A very simple helper class to streamline the buffer handling in
 // divideUpDictionaryRange.
 template<class T, size_t N>
 class AutoBuffer {
 public:
     AutoBuffer(size_t size) : buffer(stackBuffer), capacity(N) {
         if (size > N) {
             buffer = reinterpret_cast<T*>(uprv_malloc(sizeof(T)*size));
             capacity = size;
         }
     }
     ~AutoBuffer() {
         if (buffer != stackBuffer)
             uprv_free(buffer);
     }
     T* elems() {
         return buffer;
     }
     const T& operator[] (size_t i) const {
         return buffer[i];
     }
     T& operator[] (size_t i) {
         return buffer[i];
     }
     // resize without copy
     void resize(size_t size) {
         if (size <= capacity)
             return;
         if (buffer != stackBuffer)
             uprv_free(buffer);
         buffer = reinterpret_cast<T*>(uprv_malloc(sizeof(T)*size));
         capacity = size;
     }
 private:
     T stackBuffer[N];
     T* buffer;
     AutoBuffer();
     size_t capacity;
 };
 /*
  * @param text A UText representing the text
  * @param rangeStart The start of the range of dictionary characters
  * @param rangeEnd The end of the range of dictionary characters
  * @param foundBreaks Output of C array of int32_t break positions, or 0
  * @return The number of breaks found
  */
 int32_t
 CjkBreakEngine::divideUpDictionaryRange( UText *text,
         int32_t rangeStart,
         int32_t rangeEnd,
         UStack &foundBreaks ) const {
     if (rangeStart >= rangeEnd) {
         return 0;
     }
     const size_t defaultInputLength = 80;
     size_t inputLength = rangeEnd - rangeStart;
     // TODO: Replace by UnicodeString.
     AutoBuffer<UChar, defaultInputLength> charString(inputLength);
     // Normalize the input string and put it in normalizedText.
     // The map from the indices of the normalized input to the raw
     // input is kept in charPositions.
     UErrorCode status = U_ZERO_ERROR;
     utext_extract(text, rangeStart, rangeEnd, charString.elems(), inputLength, &status);
     if (U_FAILURE(status)) {
         return 0;
     }
     UnicodeString inputString(charString.elems(), inputLength);
     // TODO: Use Normalizer2.
     UNormalizationMode norm_mode = UNORM_NFKC;
     UBool isNormalized =
         Normalizer::quickCheck(inputString, norm_mode, status) == UNORM_YES ||
         Normalizer::isNormalized(inputString, norm_mode, status);
     // TODO: Replace by UVector32.
     AutoBuffer<int32_t, defaultInputLength> charPositions(inputLength + 1);
     int numChars = 0;
     UText normalizedText = UTEXT_INITIALIZER;
     // Needs to be declared here because normalizedText holds onto its buffer.
     UnicodeString normalizedString;
     if (isNormalized) {
         int32_t index = 0;
         charPositions[0] = 0;
         while(index < inputString.length()) {
             index = inputString.moveIndex32(index, 1);
             charPositions[++numChars] = index;
         }
         utext_openUnicodeString(&normalizedText, &inputString, &status);
     }
     else {
         Normalizer::normalize(inputString, norm_mode, 0, normalizedString, status);
         if (U_FAILURE(status)) {
             return 0;
         }
         charPositions.resize(normalizedString.length() + 1);
         Normalizer normalizer(charString.elems(), inputLength, norm_mode);
         int32_t index = 0;
         charPositions[0] = 0;
         while(index < normalizer.endIndex()){
             /* UChar32 uc = */ normalizer.next();
             charPositions[++numChars] = index = normalizer.getIndex();
         }
         utext_openUnicodeString(&normalizedText, &normalizedString, &status);
     }
     if (U_FAILURE(status)) {
         return 0;
     }
     // From this point on, all the indices refer to the indices of
     // the normalized input string.
     // bestSnlp[i] is the snlp of the best segmentation of the first i
     // characters in the range to be matched.
     // TODO: Replace by UVector32.
     AutoBuffer<uint32_t, defaultInputLength> bestSnlp(numChars + 1);
     bestSnlp[0] = 0;
     for(int i = 1; i <= numChars; i++) {
         bestSnlp[i] = kuint32max;
     }
     // prev[i] is the index of the last CJK character in the previous word in
     // the best segmentation of the first i characters.
     // TODO: Replace by UVector32.
     AutoBuffer<int, defaultInputLength> prev(numChars + 1);
     for(int i = 0; i <= numChars; i++){
         prev[i] = -1;
     }
     const size_t maxWordSize = 20;
     // TODO: Replace both with UVector32.
     AutoBuffer<int32_t, maxWordSize> values(numChars);
     AutoBuffer<int32_t, maxWordSize> lengths(numChars);
     // Dynamic programming to find the best segmentation.
     bool is_prev_katakana = false;
     for (int32_t i = 0; i < numChars; ++i) {
         //utext_setNativeIndex(text, rangeStart + i);
         utext_setNativeIndex(&normalizedText, i);
         if (bestSnlp[i] == kuint32max)
             continue;
         int32_t count;
         // limit maximum word length matched to size of current substring
         int32_t maxSearchLength = (i + maxWordSize < (size_t) numChars)? maxWordSize : (numChars - i);
         fDictionary->matches(&normalizedText, maxSearchLength, lengths.elems(), count, maxSearchLength, values.elems());
         // if there are no single character matches found in the dictionary
         // starting with this charcter, treat character as a 1-character word
         // with the highest value possible, i.e. the least likely to occur.
         // Exclude Korean characters from this treatment, as they should be left
         // together by default.
         if((count == 0 || lengths[0] != 1) &&
                 !fHangulWordSet.contains(utext_current32(&normalizedText))) {
             values[count] = maxSnlp;
             lengths[count++] = 1;
         }
         for (int j = 0; j < count; j++) {
             uint32_t newSnlp = bestSnlp[i] + values[j];
             if (newSnlp < bestSnlp[lengths[j] + i]) {
                 bestSnlp[lengths[j] + i] = newSnlp;
                 prev[lengths[j] + i] = i;
             }
         }
         // In Japanese,
         // Katakana word in single character is pretty rare. So we apply
         // the following heuristic to Katakana: any continuous run of Katakana
         // characters is considered a candidate word with a default cost
         // specified in the katakanaCost table according to its length.
         //utext_setNativeIndex(text, rangeStart + i);
         utext_setNativeIndex(&normalizedText, i);
         bool is_katakana = isKatakana(utext_current32(&normalizedText));
         if (!is_prev_katakana && is_katakana) {
             int j = i + 1;
             utext_next32(&normalizedText);
             // Find the end of the continuous run of Katakana characters
             while (j < numChars && (j - i) < kMaxKatakanaGroupLength &&
                     isKatakana(utext_current32(&normalizedText))) {
                 utext_next32(&normalizedText);
                 ++j;
             }
             if ((j - i) < kMaxKatakanaGroupLength) {
                 uint32_t newSnlp = bestSnlp[i] + getKatakanaCost(j - i);
                 if (newSnlp < bestSnlp[j]) {
                     bestSnlp[j] = newSnlp;
                     prev[j] = i;
                 }
             }
         }
         is_prev_katakana = is_katakana;
     }
     // Start pushing the optimal offset index into t_boundary (t for tentative).
     // prev[numChars] is guaranteed to be meaningful.
     // We'll first push in the reverse order, i.e.,
     // t_boundary[0] = numChars, and afterwards do a swap.
     // TODO: Replace by UVector32.
     AutoBuffer<int, maxWordSize> t_boundary(numChars + 1);
     int numBreaks = 0;
     // No segmentation found, set boundary to end of range
     if (bestSnlp[numChars] == kuint32max) {
         t_boundary[numBreaks++] = numChars;
     } else {
         for (int i = numChars; i > 0; i = prev[i]) {
             t_boundary[numBreaks++] = i;
         }
         U_ASSERT(prev[t_boundary[numBreaks - 1]] == 0);
     }
     // Reverse offset index in t_boundary.
     // Don't add a break for the start of the dictionary range if there is one
     // there already.
     if (foundBreaks.size() == 0 || foundBreaks.peeki() < rangeStart) {
         t_boundary[numBreaks++] = 0;
     }
     // Now that we're done, convert positions in t_bdry[] (indices in
     // the normalized input string) back to indices in the raw input string
     // while reversing t_bdry and pushing values to foundBreaks.
     for (int i = numBreaks-1; i >= 0; i--) {
         foundBreaks.push(charPositions[t_boundary[i]] + rangeStart, status);
     }
     utext_close(&normalizedText);
     return numBreaks;
 }
 #endif
 U_NAMESPACE_END
 #endif /* #if !UCONFIG_NO_BREAK_ITERATION */

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intl/icu/source/common/dictbe.cpp@6474c204b198 (annotated)

intl/icu/source/common/dictbe.cpp