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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/**
*******************************************************************************
* Copyright (C) 2006-2016, 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 "uvectr32.h"
#include "uvector.h"
#include "uassert.h"
#include "unicode/normlzr.h"
#include "cmemory.h"
#include "dictionarydata.h"
U_NAMESPACE_BEGIN
/*
******************************************************************
*/
DictionaryBreakEngine::DictionaryBreakEngine() {
}
DictionaryBreakEngine::~DictionaryBreakEngine() {
}
UBool
DictionaryBreakEngine::handles(UChar32 c) const {
return fSet.contains(c);
}
int32_t
DictionaryBreakEngine::findBreaks( UText *text,
int32_t startPos,
int32_t endPos,
UVector32 &foundBreaks ) const {
(void)startPos; // TODO: remove this param?
int32_t result = 0;
// Find the span of characters included in the set.
// The span to break begins at the current position in the text, and
// extends towards the start or end of the text, depending on 'reverse'.
int32_t start = (int32_t)utext_getNativeIndex(text);
int32_t current;
int32_t rangeStart;
int32_t rangeEnd;
UChar32 c = utext_current32(text);
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;
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.
static const int32_t POSSIBLE_WORD_LIST_MAX = 20;
class PossibleWord {
private:
// list of word candidate lengths, in increasing length order
// TODO: bytes would be sufficient for word lengths.
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
int32_t mark; // The preferred candidate's offset
int32_t current; // The candidate we're currently looking at
int32_t cuLengths[POSSIBLE_WORD_LIST_MAX]; // Word Lengths, in code units.
int32_t cpLengths[POSSIBLE_WORD_LIST_MAX]; // Word Lengths, in code points.
public:
PossibleWord() : count(0), prefix(0), offset(-1), mark(0), current(0) {};
~PossibleWord() {};
// Fill the list of candidates if needed, select the longest, and return the number found
int32_t 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
// Return value is in code points.
int32_t longestPrefix() { return prefix; };
// Mark the current candidate as the one we like
void markCurrent() { mark = current; };
// Get length in code points of the marked word.
int32_t markedCPLength() { return cpLengths[mark]; };
};
int32_t 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;
count = dict->matches(text, rangeEnd-start, UPRV_LENGTHOF(cuLengths), cuLengths, cpLengths, NULL, &prefix);
// 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+cuLengths[count-1]);
}
current = count-1;
mark = current;
return count;
}
int32_t
PossibleWord::acceptMarked( UText *text ) {
utext_setNativeIndex(text, offset + cuLengths[mark]);
return cuLengths[mark];
}
UBool
PossibleWord::backUp( UText *text ) {
if (current > 0) {
utext_setNativeIndex(text, offset + cuLengths[--current]);
return TRUE;
}
return FALSE;
}
/*
******************************************************************
* ThaiBreakEngine
*/
// How many words in a row are "good enough"?
static const int32_t THAI_LOOKAHEAD = 3;
// Will not combine a non-word with a preceding dictionary word longer than this
static const int32_t 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
static const int32_t THAI_PREFIX_COMBINE_THRESHOLD = 3;
// Ellision character
static const int32_t THAI_PAIYANNOI = 0x0E2F;
// Repeat character
static const int32_t THAI_MAIYAMOK = 0x0E46;
// Minimum word size
static const int32_t THAI_MIN_WORD = 2;
// Minimum number of characters for two words
static const int32_t THAI_MIN_WORD_SPAN = THAI_MIN_WORD * 2;
ThaiBreakEngine::ThaiBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
: DictionaryBreakEngine(),
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,
UVector32 &foundBreaks ) const {
utext_setNativeIndex(text, rangeStart);
utext_moveIndex32(text, THAI_MIN_WORD_SPAN);
if (utext_getNativeIndex(text) >= rangeEnd) {
return 0; // Not enough characters for two words
}
utext_setNativeIndex(text, rangeStart);
uint32_t wordsFound = 0;
int32_t cpWordLength = 0; // Word Length in Code Points.
int32_t cuWordLength = 0; // Word length in code units (UText native indexing)
int32_t current;
UErrorCode status = U_ZERO_ERROR;
PossibleWord words[THAI_LOOKAHEAD];
utext_setNativeIndex(text, rangeStart);
while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
cpWordLength = 0;
cuWordLength = 0;
// Look for candidate words at the current position
int32_t candidates = words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
// If we found exactly one, use that
if (candidates == 1) {
cuWordLength = words[wordsFound % THAI_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % THAI_LOOKAHEAD].markedCPLength();
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 {
int32_t 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:
// Set UText position to after the accepted word.
cuWordLength = words[wordsFound % THAI_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % THAI_LOOKAHEAD].markedCPLength();
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.
UChar32 uc = 0;
if ((int32_t)utext_getNativeIndex(text) < rangeEnd && cpWordLength < 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
&& (cuWordLength == 0
|| words[wordsFound%THAI_LOOKAHEAD].longestPrefix() < THAI_PREFIX_COMBINE_THRESHOLD)) {
// Look for a plausible word boundary
int32_t remaining = rangeEnd - (current+cuWordLength);
UChar32 pc;
int32_t chars = 0;
for (;;) {
int32_t pcIndex = (int32_t)utext_getNativeIndex(text);
pc = utext_next32(text);
int32_t pcSize = (int32_t)utext_getNativeIndex(text) - pcIndex;
chars += pcSize;
remaining -= pcSize;
if (remaining <= 0) {
break;
}
uc = utext_current32(text);
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.
int32_t num_candidates = words[(wordsFound + 1) % THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
utext_setNativeIndex(text, current + cuWordLength + chars);
if (num_candidates > 0) {
break;
}
}
}
// Bump the word count if there wasn't already one
if (cuWordLength <= 0) {
wordsFound += 1;
}
// Update the length with the passed-over characters
cuWordLength += chars;
}
else {
// Back up to where we were for next iteration
utext_setNativeIndex(text, current+cuWordLength);
}
}
// 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);
cuWordLength += (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 && cuWordLength > 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);
int32_t paiyannoiIndex = (int32_t)utext_getNativeIndex(text);
utext_next32(text);
cuWordLength += (int32_t)utext_getNativeIndex(text) - paiyannoiIndex; // 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);
int32_t maiyamokIndex = (int32_t)utext_getNativeIndex(text);
utext_next32(text);
cuWordLength += (int32_t)utext_getNativeIndex(text) - maiyamokIndex; // Add MAIYAMOK to word
}
else {
// Restore prior position
utext_next32(text);
}
}
}
else {
utext_setNativeIndex(text, current+cuWordLength);
}
}
// Did we find a word on this iteration? If so, push it on the break stack
if (cuWordLength > 0) {
foundBreaks.push((current+cuWordLength), 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"?
static const int32_t LAO_LOOKAHEAD = 3;
// Will not combine a non-word with a preceding dictionary word longer than this
static const int32_t 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
static const int32_t LAO_PREFIX_COMBINE_THRESHOLD = 3;
// Minimum word size
static const int32_t LAO_MIN_WORD = 2;
// Minimum number of characters for two words
static const int32_t LAO_MIN_WORD_SPAN = LAO_MIN_WORD * 2;
LaoBreakEngine::LaoBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
: DictionaryBreakEngine(),
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,
UVector32 &foundBreaks ) const {
if ((rangeEnd - rangeStart) < LAO_MIN_WORD_SPAN) {
return 0; // Not enough characters for two words
}
uint32_t wordsFound = 0;
int32_t cpWordLength = 0;
int32_t cuWordLength = 0;
int32_t current;
UErrorCode status = U_ZERO_ERROR;
PossibleWord words[LAO_LOOKAHEAD];
utext_setNativeIndex(text, rangeStart);
while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
cuWordLength = 0;
cpWordLength = 0;
// Look for candidate words at the current position
int32_t candidates = words[wordsFound%LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
// If we found exactly one, use that
if (candidates == 1) {
cuWordLength = words[wordsFound % LAO_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % LAO_LOOKAHEAD].markedCPLength();
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 (utext_getNativeIndex(text) >= rangeEnd) {
goto foundBest;
}
do {
int32_t 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:
cuWordLength = words[wordsFound % LAO_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % LAO_LOOKAHEAD].markedCPLength();
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 && cpWordLength < 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
&& (cuWordLength == 0
|| words[wordsFound%LAO_LOOKAHEAD].longestPrefix() < LAO_PREFIX_COMBINE_THRESHOLD)) {
// Look for a plausible word boundary
int32_t remaining = rangeEnd - (current + cuWordLength);
UChar32 pc;
UChar32 uc;
int32_t chars = 0;
for (;;) {
int32_t pcIndex = (int32_t)utext_getNativeIndex(text);
pc = utext_next32(text);
int32_t pcSize = (int32_t)utext_getNativeIndex(text) - pcIndex;
chars += pcSize;
remaining -= pcSize;
if (remaining <= 0) {
break;
}
uc = utext_current32(text);
if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
// Maybe. See if it's in the dictionary.
// TODO: this looks iffy; compare with old code.
int32_t num_candidates = words[(wordsFound + 1) % LAO_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
utext_setNativeIndex(text, current + cuWordLength + chars);
if (num_candidates > 0) {
break;
}
}
}
// Bump the word count if there wasn't already one
if (cuWordLength <= 0) {
wordsFound += 1;
}
// Update the length with the passed-over characters
cuWordLength += chars;
}
else {
// Back up to where we were for next iteration
utext_setNativeIndex(text, current + cuWordLength);
}
}
// 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);
cuWordLength += (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 (cuWordLength > 0) {
foundBreaks.push((current+cuWordLength), 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;
}
/*
******************************************************************
* BurmeseBreakEngine
*/
// How many words in a row are "good enough"?
static const int32_t BURMESE_LOOKAHEAD = 3;
// Will not combine a non-word with a preceding dictionary word longer than this
static const int32_t BURMESE_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
static const int32_t BURMESE_PREFIX_COMBINE_THRESHOLD = 3;
// Minimum word size
static const int32_t BURMESE_MIN_WORD = 2;
// Minimum number of characters for two words
static const int32_t BURMESE_MIN_WORD_SPAN = BURMESE_MIN_WORD * 2;
BurmeseBreakEngine::BurmeseBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
: DictionaryBreakEngine(),
fDictionary(adoptDictionary)
{
fBurmeseWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Mymr:]&[:LineBreak=SA:]]"), status);
if (U_SUCCESS(status)) {
setCharacters(fBurmeseWordSet);
}
fMarkSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Mymr:]&[:LineBreak=SA:]&[:M:]]"), status);
fMarkSet.add(0x0020);
fEndWordSet = fBurmeseWordSet;
fBeginWordSet.add(0x1000, 0x102A); // basic consonants and independent vowels
// Compact for caching.
fMarkSet.compact();
fEndWordSet.compact();
fBeginWordSet.compact();
}
BurmeseBreakEngine::~BurmeseBreakEngine() {
delete fDictionary;
}
int32_t
BurmeseBreakEngine::divideUpDictionaryRange( UText *text,
int32_t rangeStart,
int32_t rangeEnd,
UVector32 &foundBreaks ) const {
if ((rangeEnd - rangeStart) < BURMESE_MIN_WORD_SPAN) {
return 0; // Not enough characters for two words
}
uint32_t wordsFound = 0;
int32_t cpWordLength = 0;
int32_t cuWordLength = 0;
int32_t current;
UErrorCode status = U_ZERO_ERROR;
PossibleWord words[BURMESE_LOOKAHEAD];
utext_setNativeIndex(text, rangeStart);
while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
cuWordLength = 0;
cpWordLength = 0;
// Look for candidate words at the current position
int32_t candidates = words[wordsFound%BURMESE_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
// If we found exactly one, use that
if (candidates == 1) {
cuWordLength = words[wordsFound % BURMESE_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % BURMESE_LOOKAHEAD].markedCPLength();
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 (utext_getNativeIndex(text) >= rangeEnd) {
goto foundBest;
}
do {
int32_t wordsMatched = 1;
if (words[(wordsFound + 1) % BURMESE_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) > 0) {
if (wordsMatched < 2) {
// Followed by another dictionary word; mark first word as a good candidate
words[wordsFound%BURMESE_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) % BURMESE_LOOKAHEAD].candidates(text, fDictionary, rangeEnd)) {
words[wordsFound % BURMESE_LOOKAHEAD].markCurrent();
goto foundBest;
}
}
while (words[(wordsFound + 1) % BURMESE_LOOKAHEAD].backUp(text));
}
}
while (words[wordsFound % BURMESE_LOOKAHEAD].backUp(text));
foundBest:
cuWordLength = words[wordsFound % BURMESE_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % BURMESE_LOOKAHEAD].markedCPLength();
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 && cpWordLength < BURMESE_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 % BURMESE_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0
&& (cuWordLength == 0
|| words[wordsFound%BURMESE_LOOKAHEAD].longestPrefix() < BURMESE_PREFIX_COMBINE_THRESHOLD)) {
// Look for a plausible word boundary
int32_t remaining = rangeEnd - (current + cuWordLength);
UChar32 pc;
UChar32 uc;
int32_t chars = 0;
for (;;) {
int32_t pcIndex = (int32_t)utext_getNativeIndex(text);
pc = utext_next32(text);
int32_t pcSize = (int32_t)utext_getNativeIndex(text) - pcIndex;
chars += pcSize;
remaining -= pcSize;
if (remaining <= 0) {
break;
}
uc = utext_current32(text);
if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
// Maybe. See if it's in the dictionary.
// TODO: this looks iffy; compare with old code.
int32_t num_candidates = words[(wordsFound + 1) % BURMESE_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
utext_setNativeIndex(text, current + cuWordLength + chars);
if (num_candidates > 0) {
break;
}
}
}
// Bump the word count if there wasn't already one
if (cuWordLength <= 0) {
wordsFound += 1;
}
// Update the length with the passed-over characters
cuWordLength += chars;
}
else {
// Back up to where we were for next iteration
utext_setNativeIndex(text, current + cuWordLength);
}
}
// 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);
cuWordLength += (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 BURMESE
// Did we find a word on this iteration? If so, push it on the break stack
if (cuWordLength > 0) {
foundBreaks.push((current+cuWordLength), 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"?
static const int32_t KHMER_LOOKAHEAD = 3;
// Will not combine a non-word with a preceding dictionary word longer than this
static const int32_t KHMER_ROOT_COMBINE_THRESHOLD = 10;
// Will not combine a non-word that shares at least this much prefix with a
// dictionary word, with a preceding word
static const int32_t KHMER_PREFIX_COMBINE_THRESHOLD = 5;
// Minimum word size
static const int32_t KHMER_MIN_WORD = 2;
// Minimum number of characters for two words
static const int32_t KHMER_MIN_WORD_SPAN = KHMER_MIN_WORD * 2;
KhmerBreakEngine::KhmerBreakEngine(DictionaryMatcher *adoptDictionary, UErrorCode &status)
: DictionaryBreakEngine(),
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,
UVector32 &foundBreaks ) const {
if ((rangeEnd - rangeStart) < KHMER_MIN_WORD_SPAN) {
return 0; // Not enough characters for two words
}
uint32_t wordsFound = 0;
int32_t cpWordLength = 0;
int32_t cuWordLength = 0;
int32_t current;
UErrorCode status = U_ZERO_ERROR;
PossibleWord words[KHMER_LOOKAHEAD];
utext_setNativeIndex(text, rangeStart);
while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) {
cuWordLength = 0;
cpWordLength = 0;
// Look for candidate words at the current position
int32_t candidates = words[wordsFound%KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
// If we found exactly one, use that
if (candidates == 1) {
cuWordLength = words[wordsFound % KHMER_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % KHMER_LOOKAHEAD].markedCPLength();
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 {
int32_t 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:
cuWordLength = words[wordsFound % KHMER_LOOKAHEAD].acceptMarked(text);
cpWordLength = words[wordsFound % KHMER_LOOKAHEAD].markedCPLength();
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 && cpWordLength < 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
&& (cuWordLength == 0
|| words[wordsFound % KHMER_LOOKAHEAD].longestPrefix() < KHMER_PREFIX_COMBINE_THRESHOLD)) {
// Look for a plausible word boundary
int32_t remaining = rangeEnd - (current+cuWordLength);
UChar32 pc;
UChar32 uc;
int32_t chars = 0;
for (;;) {
int32_t pcIndex = (int32_t)utext_getNativeIndex(text);
pc = utext_next32(text);
int32_t pcSize = (int32_t)utext_getNativeIndex(text) - pcIndex;
chars += pcSize;
remaining -= pcSize;
if (remaining <= 0) {
break;
}
uc = utext_current32(text);
if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) {
// Maybe. See if it's in the dictionary.
int32_t num_candidates = words[(wordsFound + 1) % KHMER_LOOKAHEAD].candidates(text, fDictionary, rangeEnd);
utext_setNativeIndex(text, current+cuWordLength+chars);
if (num_candidates > 0) {
break;
}
}
}
// Bump the word count if there wasn't already one
if (cuWordLength <= 0) {
wordsFound += 1;
}
// Update the length with the passed-over characters
cuWordLength += chars;
}
else {
// Back up to where we were for next iteration
utext_setNativeIndex(text, current+cuWordLength);
}
}
// 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);
cuWordLength += (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 (cuWordLength > 0) {
foundBreaks.push((current+cuWordLength), 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(), 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);
nfkcNorm2 = Normalizer2::getNFKCInstance(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 int32_t kMaxKatakanaLength = 8;
static const int32_t kMaxKatakanaGroupLength = 20;
static const uint32_t maxSnlp = 255;
static inline uint32_t getKatakanaCost(int32_t 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(UChar32 value) {
return (value >= 0x30A1 && value <= 0x30FE && value != 0x30FB) ||
(value >= 0xFF66 && value <= 0xFF9f);
}
// Function for accessing internal utext flags.
// Replicates an internal UText function.
static inline int32_t utext_i32_flag(int32_t bitIndex) {
return (int32_t)1 << bitIndex;
}
/*
* @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 vector<int32> to receive the break positions
* @return The number of breaks found
*/
int32_t
CjkBreakEngine::divideUpDictionaryRange( UText *inText,
int32_t rangeStart,
int32_t rangeEnd,
UVector32 &foundBreaks ) const {
if (rangeStart >= rangeEnd) {
return 0;
}
// UnicodeString version of input UText, NFKC normalized if necessary.
UnicodeString inString;
// inputMap[inStringIndex] = corresponding native index from UText inText.
// If NULL then mapping is 1:1
LocalPointer<UVector32> inputMap;
UErrorCode status = U_ZERO_ERROR;
// if UText has the input string as one contiguous UTF-16 chunk
if ((inText->providerProperties & utext_i32_flag(UTEXT_PROVIDER_STABLE_CHUNKS)) &&
inText->chunkNativeStart <= rangeStart &&
inText->chunkNativeLimit >= rangeEnd &&
inText->nativeIndexingLimit >= rangeEnd - inText->chunkNativeStart) {
// Input UText is in one contiguous UTF-16 chunk.
// Use Read-only aliasing UnicodeString.
inString.setTo(FALSE,
inText->chunkContents + rangeStart - inText->chunkNativeStart,
rangeEnd - rangeStart);
} else {
// Copy the text from the original inText (UText) to inString (UnicodeString).
// Create a map from UnicodeString indices -> UText offsets.
utext_setNativeIndex(inText, rangeStart);
int32_t limit = rangeEnd;
U_ASSERT(limit <= utext_nativeLength(inText));
if (limit > utext_nativeLength(inText)) {
limit = (int32_t)utext_nativeLength(inText);
}
inputMap.adoptInsteadAndCheckErrorCode(new UVector32(status), status);
if (U_FAILURE(status)) {
return 0;
}
while (utext_getNativeIndex(inText) < limit) {
int32_t nativePosition = (int32_t)utext_getNativeIndex(inText);
UChar32 c = utext_next32(inText);
U_ASSERT(c != U_SENTINEL);
inString.append(c);
while (inputMap->size() < inString.length()) {
inputMap->addElement(nativePosition, status);
}
}
inputMap->addElement(limit, status);
}
if (!nfkcNorm2->isNormalized(inString, status)) {
UnicodeString normalizedInput;
// normalizedMap[normalizedInput position] == original UText position.
LocalPointer<UVector32> normalizedMap(new UVector32(status), status);
if (U_FAILURE(status)) {
return 0;
}
UnicodeString fragment;
UnicodeString normalizedFragment;
for (int32_t srcI = 0; srcI < inString.length();) { // Once per normalization chunk
fragment.remove();
int32_t fragmentStartI = srcI;
UChar32 c = inString.char32At(srcI);
for (;;) {
fragment.append(c);
srcI = inString.moveIndex32(srcI, 1);
if (srcI == inString.length()) {
break;
}
c = inString.char32At(srcI);
if (nfkcNorm2->hasBoundaryBefore(c)) {
break;
}
}
nfkcNorm2->normalize(fragment, normalizedFragment, status);
normalizedInput.append(normalizedFragment);
// Map every position in the normalized chunk to the start of the chunk
// in the original input.
int32_t fragmentOriginalStart = inputMap.isValid() ?
inputMap->elementAti(fragmentStartI) : fragmentStartI+rangeStart;
while (normalizedMap->size() < normalizedInput.length()) {
normalizedMap->addElement(fragmentOriginalStart, status);
if (U_FAILURE(status)) {
break;
}
}
}
U_ASSERT(normalizedMap->size() == normalizedInput.length());
int32_t nativeEnd = inputMap.isValid() ?
inputMap->elementAti(inString.length()) : inString.length()+rangeStart;
normalizedMap->addElement(nativeEnd, status);
inputMap.moveFrom(normalizedMap);
inString.moveFrom(normalizedInput);
}
int32_t numCodePts = inString.countChar32();
if (numCodePts != inString.length()) {
// There are supplementary characters in the input.
// The dictionary will produce boundary positions in terms of code point indexes,
// not in terms of code unit string indexes.
// Use the inputMap mechanism to take care of this in addition to indexing differences
// from normalization and/or UTF-8 input.
UBool hadExistingMap = inputMap.isValid();
if (!hadExistingMap) {
inputMap.adoptInsteadAndCheckErrorCode(new UVector32(status), status);
if (U_FAILURE(status)) {
return 0;
}
}
int32_t cpIdx = 0;
for (int32_t cuIdx = 0; ; cuIdx = inString.moveIndex32(cuIdx, 1)) {
U_ASSERT(cuIdx >= cpIdx);
if (hadExistingMap) {
inputMap->setElementAt(inputMap->elementAti(cuIdx), cpIdx);
} else {
inputMap->addElement(cuIdx+rangeStart, status);
}
cpIdx++;
if (cuIdx == inString.length()) {
break;
}
}
}
// bestSnlp[i] is the snlp of the best segmentation of the first i
// code points in the range to be matched.
UVector32 bestSnlp(numCodePts + 1, status);
bestSnlp.addElement(0, status);
for(int32_t i = 1; i <= numCodePts; i++) {
bestSnlp.addElement(kuint32max, status);
}
// prev[i] is the index of the last CJK code point in the previous word in
// the best segmentation of the first i characters.
UVector32 prev(numCodePts + 1, status);
for(int32_t i = 0; i <= numCodePts; i++){
prev.addElement(-1, status);
}
const int32_t maxWordSize = 20;
UVector32 values(numCodePts, status);
values.setSize(numCodePts);
UVector32 lengths(numCodePts, status);
lengths.setSize(numCodePts);
UText fu = UTEXT_INITIALIZER;
utext_openUnicodeString(&fu, &inString, &status);
// Dynamic programming to find the best segmentation.
// In outer loop, i is the code point index,
// ix is the corresponding string (code unit) index.
// They differ when the string contains supplementary characters.
int32_t ix = 0;
bool is_prev_katakana = false;
for (int32_t i = 0; i < numCodePts; ++i, ix = inString.moveIndex32(ix, 1)) {
if ((uint32_t)bestSnlp.elementAti(i) == kuint32max) {
continue;
}
int32_t count;
utext_setNativeIndex(&fu, ix);
count = fDictionary->matches(&fu, maxWordSize, numCodePts,
NULL, lengths.getBuffer(), values.getBuffer(), NULL);
// Note: lengths is filled with code point lengths
// The NULL parameter is the ignored code unit lengths.
// if there are no single character matches found in the dictionary
// starting with this character, 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.elementAti(0) != 1) &&
!fHangulWordSet.contains(inString.char32At(ix))) {
values.setElementAt(maxSnlp, count); // 255
lengths.setElementAt(1, count++);
}
for (int32_t j = 0; j < count; j++) {
uint32_t newSnlp = (uint32_t)bestSnlp.elementAti(i) + (uint32_t)values.elementAti(j);
int32_t ln_j_i = lengths.elementAti(j) + i;
if (newSnlp < (uint32_t)bestSnlp.elementAti(ln_j_i)) {
bestSnlp.setElementAt(newSnlp, ln_j_i);
prev.setElementAt(i, ln_j_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.
bool is_katakana = isKatakana(inString.char32At(ix));
int32_t katakanaRunLength = 1;
if (!is_prev_katakana && is_katakana) {
int32_t j = inString.moveIndex32(ix, 1);
// Find the end of the continuous run of Katakana characters
while (j < inString.length() && katakanaRunLength < kMaxKatakanaGroupLength &&
isKatakana(inString.char32At(j))) {
j = inString.moveIndex32(j, 1);
katakanaRunLength++;
}
if (katakanaRunLength < kMaxKatakanaGroupLength) {
uint32_t newSnlp = bestSnlp.elementAti(i) + getKatakanaCost(katakanaRunLength);
if (newSnlp < (uint32_t)bestSnlp.elementAti(i+katakanaRunLength)) {
bestSnlp.setElementAt(newSnlp, i+katakanaRunLength);
prev.setElementAt(i, i+katakanaRunLength); // prev[j] = i;
}
}
}
is_prev_katakana = is_katakana;
}
utext_close(&fu);
// Start pushing the optimal offset index into t_boundary (t for tentative).
// prev[numCodePts] is guaranteed to be meaningful.
// We'll first push in the reverse order, i.e.,
// t_boundary[0] = numCodePts, and afterwards do a swap.
UVector32 t_boundary(numCodePts+1, status);
int32_t numBreaks = 0;
// No segmentation found, set boundary to end of range
if ((uint32_t)bestSnlp.elementAti(numCodePts) == kuint32max) {
t_boundary.addElement(numCodePts, status);
numBreaks++;
} else {
for (int32_t i = numCodePts; i > 0; i = prev.elementAti(i)) {
t_boundary.addElement(i, status);
numBreaks++;
}
U_ASSERT(prev.elementAti(t_boundary.elementAti(numBreaks - 1)) == 0);
}
// Add a break for the start of the dictionary range if there is not one
// there already.
if (foundBreaks.size() == 0 || foundBreaks.peeki() < rangeStart) {
t_boundary.addElement(0, status);
numBreaks++;
}
// Now that we're done, convert positions in t_boundary[] (indices in
// the normalized input string) back to indices in the original input UText
// while reversing t_boundary and pushing values to foundBreaks.
int32_t prevCPPos = -1;
int32_t prevUTextPos = -1;
for (int32_t i = numBreaks-1; i >= 0; i--) {
int32_t cpPos = t_boundary.elementAti(i);
U_ASSERT(cpPos > prevCPPos);
int32_t utextPos = inputMap.isValid() ? inputMap->elementAti(cpPos) : cpPos + rangeStart;
U_ASSERT(utextPos >= prevUTextPos);
if (utextPos > prevUTextPos) {
// Boundaries are added to foundBreaks output in ascending order.
U_ASSERT(foundBreaks.size() == 0 || foundBreaks.peeki() < utextPos);
foundBreaks.push(utextPos, status);
} else {
// Normalization expanded the input text, the dictionary found a boundary
// within the expansion, giving two boundaries with the same index in the
// original text. Ignore the second. See ticket #12918.
--numBreaks;
}
prevCPPos = cpPos;
prevUTextPos = utextPos;
}
(void)prevCPPos; // suppress compiler warnings about unused variable
// inString goes out of scope
// inputMap goes out of scope
return numBreaks;
}
#endif
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_BREAK_ITERATION */