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Diffstat (limited to 'intl/icu/source/common/ubidiln.cpp')
| -rw-r--r-- | intl/icu/source/common/ubidiln.cpp | 1347 |
1 files changed, 1347 insertions, 0 deletions
diff --git a/intl/icu/source/common/ubidiln.cpp b/intl/icu/source/common/ubidiln.cpp new file mode 100644 index 0000000000..63c4f9190a --- /dev/null +++ b/intl/icu/source/common/ubidiln.cpp @@ -0,0 +1,1347 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +****************************************************************************** +* +* Copyright (C) 1999-2015, International Business Machines +* Corporation and others. All Rights Reserved. +* +****************************************************************************** +* file name: ubidiln.c +* encoding: UTF-8 +* tab size: 8 (not used) +* indentation:4 +* +* created on: 1999aug06 +* created by: Markus W. Scherer, updated by Matitiahu Allouche +*/ + +#include "cmemory.h" +#include "unicode/utypes.h" +#include "unicode/ustring.h" +#include "unicode/uchar.h" +#include "unicode/ubidi.h" +#include "ubidiimp.h" +#include "uassert.h" + +/* + * General remarks about the functions in this file: + * + * These functions deal with the aspects of potentially mixed-directional + * text in a single paragraph or in a line of a single paragraph + * which has already been processed according to + * the Unicode 6.3 BiDi algorithm as defined in + * https://www.unicode.org/reports/tr9/ , version 28, + * also described in The Unicode Standard, Version 6.3.0 . + * + * This means that there is a UBiDi object with a levels + * and a dirProps array. + * paraLevel and direction are also set. + * Only if the length of the text is zero, then levels==dirProps==nullptr. + * + * The overall directionality of the paragraph + * or line is used to bypass the reordering steps if possible. + * Even purely RTL text does not need reordering there because + * the ubidi_getLogical/VisualIndex() functions can compute the + * index on the fly in such a case. + * + * The implementation of the access to same-level-runs and of the reordering + * do attempt to provide better performance and less memory usage compared to + * a direct implementation of especially rule (L2) with an array of + * one (32-bit) integer per text character. + * + * Here, the levels array is scanned as soon as necessary, and a vector of + * same-level-runs is created. Reordering then is done on this vector. + * For each run of text positions that were resolved to the same level, + * only 8 bytes are stored: the first text position of the run and the visual + * position behind the run after reordering. + * One sign bit is used to hold the directionality of the run. + * This is inefficient if there are many very short runs. If the average run + * length is <2, then this uses more memory. + * + * In a further attempt to save memory, the levels array is never changed + * after all the resolution rules (Xn, Wn, Nn, In). + * Many functions have to consider the field trailingWSStart: + * if it is less than length, then there is an implicit trailing run + * at the paraLevel, + * which is not reflected in the levels array. + * This allows a line UBiDi object to use the same levels array as + * its paragraph parent object. + * + * When a UBiDi object is created for a line of a paragraph, then the + * paragraph's levels and dirProps arrays are reused by way of setting + * a pointer into them, not by copying. This again saves memory and forbids to + * change the now shared levels for (L1). + */ + +/* handle trailing WS (L1) -------------------------------------------------- */ + +/* + * setTrailingWSStart() sets the start index for a trailing + * run of WS in the line. This is necessary because we do not modify + * the paragraph's levels array that we just point into. + * Using trailingWSStart is another form of performing (L1). + * + * To make subsequent operations easier, we also include the run + * before the WS if it is at the paraLevel - we merge the two here. + * + * This function is called only from ubidi_setLine(), so pBiDi->paraLevel is + * set correctly for the line even when contextual multiple paragraphs. + */ +static void +setTrailingWSStart(UBiDi *pBiDi) { + /* pBiDi->direction!=UBIDI_MIXED */ + + const DirProp *dirProps=pBiDi->dirProps; + UBiDiLevel *levels=pBiDi->levels; + int32_t start=pBiDi->length; + UBiDiLevel paraLevel=pBiDi->paraLevel; + + /* If the line is terminated by a block separator, all preceding WS etc... + are already set to paragraph level. + Setting trailingWSStart to pBidi->length will avoid changing the + level of B chars from 0 to paraLevel in ubidi_getLevels when + orderParagraphsLTR==true. + */ + if(dirProps[start-1]==B) { + pBiDi->trailingWSStart=start; /* currently == pBiDi->length */ + return; + } + /* go backwards across all WS, BN, explicit codes */ + while(start>0 && DIRPROP_FLAG(dirProps[start-1])&MASK_WS) { + --start; + } + + /* if the WS run can be merged with the previous run then do so here */ + while(start>0 && levels[start-1]==paraLevel) { + --start; + } + + pBiDi->trailingWSStart=start; +} + +/* ubidi_setLine ------------------------------------------------------------ */ + +U_CAPI void U_EXPORT2 +ubidi_setLine(const UBiDi *pParaBiDi, + int32_t start, int32_t limit, + UBiDi *pLineBiDi, + UErrorCode *pErrorCode) { + int32_t length; + + /* check the argument values */ + RETURN_VOID_IF_NULL_OR_FAILING_ERRCODE(pErrorCode); + RETURN_VOID_IF_NOT_VALID_PARA(pParaBiDi, *pErrorCode); + RETURN_VOID_IF_BAD_RANGE(start, 0, limit, *pErrorCode); + RETURN_VOID_IF_BAD_RANGE(limit, 0, pParaBiDi->length+1, *pErrorCode); + if(pLineBiDi==nullptr) { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return; + } + if(ubidi_getParagraph(pParaBiDi, start, nullptr, nullptr, nullptr, pErrorCode) != + ubidi_getParagraph(pParaBiDi, limit-1, nullptr, nullptr, nullptr, pErrorCode)) { + /* the line crosses a paragraph boundary */ + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return; + } + + /* set the values in pLineBiDi from its pParaBiDi parent */ + pLineBiDi->pParaBiDi=nullptr; /* mark unfinished setLine */ + pLineBiDi->text=pParaBiDi->text+start; + length=pLineBiDi->length=limit-start; + pLineBiDi->resultLength=pLineBiDi->originalLength=length; + pLineBiDi->paraLevel=GET_PARALEVEL(pParaBiDi, start); + pLineBiDi->paraCount=pParaBiDi->paraCount; + pLineBiDi->runs=nullptr; + pLineBiDi->flags=0; + pLineBiDi->reorderingMode=pParaBiDi->reorderingMode; + pLineBiDi->reorderingOptions=pParaBiDi->reorderingOptions; + pLineBiDi->controlCount=0; + if(pParaBiDi->controlCount>0) { + int32_t j; + for(j=start; j<limit; j++) { + if(IS_BIDI_CONTROL_CHAR(pParaBiDi->text[j])) { + pLineBiDi->controlCount++; + } + } + pLineBiDi->resultLength-=pLineBiDi->controlCount; + } + + pLineBiDi->dirProps=pParaBiDi->dirProps+start; + pLineBiDi->levels=pParaBiDi->levels+start; + pLineBiDi->runCount=-1; + + if(pParaBiDi->direction!=UBIDI_MIXED) { + /* the parent is already trivial */ + pLineBiDi->direction=pParaBiDi->direction; + + /* + * The parent's levels are all either + * implicitly or explicitly ==paraLevel; + * do the same here. + */ + if(pParaBiDi->trailingWSStart<=start) { + pLineBiDi->trailingWSStart=0; + } else if(pParaBiDi->trailingWSStart<limit) { + pLineBiDi->trailingWSStart=pParaBiDi->trailingWSStart-start; + } else { + pLineBiDi->trailingWSStart=length; + } + } else { + const UBiDiLevel *levels=pLineBiDi->levels; + int32_t i, trailingWSStart; + UBiDiLevel level; + + setTrailingWSStart(pLineBiDi); + trailingWSStart=pLineBiDi->trailingWSStart; + + /* recalculate pLineBiDi->direction */ + if(trailingWSStart==0) { + /* all levels are at paraLevel */ + pLineBiDi->direction=(UBiDiDirection)(pLineBiDi->paraLevel&1); + } else { + /* get the level of the first character */ + level=(UBiDiLevel)(levels[0]&1); + + /* if there is anything of a different level, then the line is mixed */ + if(trailingWSStart<length && (pLineBiDi->paraLevel&1)!=level) { + /* the trailing WS is at paraLevel, which differs from levels[0] */ + pLineBiDi->direction=UBIDI_MIXED; + } else { + /* see if levels[1..trailingWSStart-1] have the same direction as levels[0] and paraLevel */ + i=1; + for(;;) { + if(i==trailingWSStart) { + /* the direction values match those in level */ + pLineBiDi->direction=(UBiDiDirection)level; + break; + } else if((levels[i]&1)!=level) { + pLineBiDi->direction=UBIDI_MIXED; + break; + } + ++i; + } + } + } + + switch(pLineBiDi->direction) { + case UBIDI_LTR: + /* make sure paraLevel is even */ + pLineBiDi->paraLevel=(UBiDiLevel)((pLineBiDi->paraLevel+1)&~1); + + /* all levels are implicitly at paraLevel (important for ubidi_getLevels()) */ + pLineBiDi->trailingWSStart=0; + break; + case UBIDI_RTL: + /* make sure paraLevel is odd */ + pLineBiDi->paraLevel|=1; + + /* all levels are implicitly at paraLevel (important for ubidi_getLevels()) */ + pLineBiDi->trailingWSStart=0; + break; + default: + break; + } + } + pLineBiDi->pParaBiDi=pParaBiDi; /* mark successful setLine */ + return; +} + +U_CAPI UBiDiLevel U_EXPORT2 +ubidi_getLevelAt(const UBiDi *pBiDi, int32_t charIndex) { + /* return paraLevel if in the trailing WS run, otherwise the real level */ + if(!IS_VALID_PARA_OR_LINE(pBiDi) || charIndex<0 || pBiDi->length<=charIndex) { + return 0; + } else if(pBiDi->direction!=UBIDI_MIXED || charIndex>=pBiDi->trailingWSStart) { + return GET_PARALEVEL(pBiDi, charIndex); + } else { + return pBiDi->levels[charIndex]; + } +} + +U_CAPI const UBiDiLevel * U_EXPORT2 +ubidi_getLevels(UBiDi *pBiDi, UErrorCode *pErrorCode) { + int32_t start, length; + + RETURN_IF_NULL_OR_FAILING_ERRCODE(pErrorCode, nullptr); + RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, *pErrorCode, nullptr); + if((length=pBiDi->length)<=0) { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return nullptr; + } + if((start=pBiDi->trailingWSStart)==length) { + /* the current levels array reflects the WS run */ + return pBiDi->levels; + } + + /* + * After the previous if(), we know that the levels array + * has an implicit trailing WS run and therefore does not fully + * reflect itself all the levels. + * This must be a UBiDi object for a line, and + * we need to create a new levels array. + */ + if(getLevelsMemory(pBiDi, length)) { + UBiDiLevel *levels=pBiDi->levelsMemory; + + if(start>0 && levels!=pBiDi->levels) { + uprv_memcpy(levels, pBiDi->levels, start); + } + /* pBiDi->paraLevel is ok even if contextual multiple paragraphs, + since pBidi is a line object */ + uprv_memset(levels+start, pBiDi->paraLevel, length-start); + + /* this new levels array is set for the line and reflects the WS run */ + pBiDi->trailingWSStart=length; + return pBiDi->levels=levels; + } else { + /* out of memory */ + *pErrorCode=U_MEMORY_ALLOCATION_ERROR; + return nullptr; + } +} + +U_CAPI void U_EXPORT2 +ubidi_getLogicalRun(const UBiDi *pBiDi, int32_t logicalPosition, + int32_t *pLogicalLimit, UBiDiLevel *pLevel) { + UErrorCode errorCode; + int32_t runCount, visualStart, logicalLimit, logicalFirst, i; + Run iRun; + + errorCode=U_ZERO_ERROR; + RETURN_VOID_IF_BAD_RANGE(logicalPosition, 0, pBiDi->length, errorCode); + /* ubidi_countRuns will check VALID_PARA_OR_LINE */ + runCount=ubidi_countRuns((UBiDi *)pBiDi, &errorCode); + if(U_FAILURE(errorCode)) { + return; + } + /* this is done based on runs rather than on levels since levels have + a special interpretation when UBIDI_REORDER_RUNS_ONLY + */ + visualStart=logicalLimit=0; + iRun=pBiDi->runs[0]; + + for(i=0; i<runCount; i++) { + iRun = pBiDi->runs[i]; + logicalFirst=GET_INDEX(iRun.logicalStart); + logicalLimit=logicalFirst+iRun.visualLimit-visualStart; + if((logicalPosition>=logicalFirst) && + (logicalPosition<logicalLimit)) { + break; + } + visualStart = iRun.visualLimit; + } + if(pLogicalLimit) { + *pLogicalLimit=logicalLimit; + } + if(pLevel) { + if(pBiDi->reorderingMode==UBIDI_REORDER_RUNS_ONLY) { + *pLevel=(UBiDiLevel)GET_ODD_BIT(iRun.logicalStart); + } + else if(pBiDi->direction!=UBIDI_MIXED || logicalPosition>=pBiDi->trailingWSStart) { + *pLevel=GET_PARALEVEL(pBiDi, logicalPosition); + } else { + *pLevel=pBiDi->levels[logicalPosition]; + } + } +} + +/* runs API functions ------------------------------------------------------- */ + +U_CAPI int32_t U_EXPORT2 +ubidi_countRuns(UBiDi *pBiDi, UErrorCode *pErrorCode) { + RETURN_IF_NULL_OR_FAILING_ERRCODE(pErrorCode, -1); + RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, *pErrorCode, -1); + ubidi_getRuns(pBiDi, pErrorCode); + if(U_FAILURE(*pErrorCode)) { + return -1; + } + return pBiDi->runCount; +} + +U_CAPI UBiDiDirection U_EXPORT2 +ubidi_getVisualRun(UBiDi *pBiDi, int32_t runIndex, + int32_t *pLogicalStart, int32_t *pLength) +{ + int32_t start; + UErrorCode errorCode = U_ZERO_ERROR; + RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, errorCode, UBIDI_LTR); + ubidi_getRuns(pBiDi, &errorCode); + if(U_FAILURE(errorCode)) { + return UBIDI_LTR; + } + RETURN_IF_BAD_RANGE(runIndex, 0, pBiDi->runCount, errorCode, UBIDI_LTR); + + start=pBiDi->runs[runIndex].logicalStart; + if(pLogicalStart!=nullptr) { + *pLogicalStart=GET_INDEX(start); + } + if(pLength!=nullptr) { + if(runIndex>0) { + *pLength=pBiDi->runs[runIndex].visualLimit- + pBiDi->runs[runIndex-1].visualLimit; + } else { + *pLength=pBiDi->runs[0].visualLimit; + } + } + return (UBiDiDirection)GET_ODD_BIT(start); +} + +/* in trivial cases there is only one trivial run; called by ubidi_getRuns() */ +static void +getSingleRun(UBiDi *pBiDi, UBiDiLevel level) { + /* simple, single-run case */ + pBiDi->runs=pBiDi->simpleRuns; + pBiDi->runCount=1; + + /* fill and reorder the single run */ + pBiDi->runs[0].logicalStart=MAKE_INDEX_ODD_PAIR(0, level); + pBiDi->runs[0].visualLimit=pBiDi->length; + pBiDi->runs[0].insertRemove=0; +} + +/* reorder the runs array (L2) ---------------------------------------------- */ + +/* + * Reorder the same-level runs in the runs array. + * Here, runCount>1 and maxLevel>=minLevel>=paraLevel. + * All the visualStart fields=logical start before reordering. + * The "odd" bits are not set yet. + * + * Reordering with this data structure lends itself to some handy shortcuts: + * + * Since each run is moved but not modified, and since at the initial maxLevel + * each sequence of same-level runs consists of only one run each, we + * don't need to do anything there and can predecrement maxLevel. + * In many simple cases, the reordering is thus done entirely in the + * index mapping. + * Also, reordering occurs only down to the lowest odd level that occurs, + * which is minLevel|1. However, if the lowest level itself is odd, then + * in the last reordering the sequence of the runs at this level or higher + * will be all runs, and we don't need the elaborate loop to search for them. + * This is covered by ++minLevel instead of minLevel|=1 followed + * by an extra reorder-all after the reorder-some loop. + * About a trailing WS run: + * Such a run would need special treatment because its level is not + * reflected in levels[] if this is not a paragraph object. + * Instead, all characters from trailingWSStart on are implicitly at + * paraLevel. + * However, for all maxLevel>paraLevel, this run will never be reordered + * and does not need to be taken into account. maxLevel==paraLevel is only reordered + * if minLevel==paraLevel is odd, which is done in the extra segment. + * This means that for the main reordering loop we don't need to consider + * this run and can --runCount. If it is later part of the all-runs + * reordering, then runCount is adjusted accordingly. + */ +static void +reorderLine(UBiDi *pBiDi, UBiDiLevel minLevel, UBiDiLevel maxLevel) { + Run *runs, tempRun; + UBiDiLevel *levels; + int32_t firstRun, endRun, limitRun, runCount; + + /* nothing to do? */ + if(maxLevel<=(minLevel|1)) { + return; + } + + /* + * Reorder only down to the lowest odd level + * and reorder at an odd minLevel in a separate, simpler loop. + * See comments above for why minLevel is always incremented. + */ + ++minLevel; + + runs=pBiDi->runs; + levels=pBiDi->levels; + runCount=pBiDi->runCount; + + /* do not include the WS run at paraLevel<=old minLevel except in the simple loop */ + if(pBiDi->trailingWSStart<pBiDi->length) { + --runCount; + } + + while(--maxLevel>=minLevel) { + firstRun=0; + + /* loop for all sequences of runs */ + for(;;) { + /* look for a sequence of runs that are all at >=maxLevel */ + /* look for the first run of such a sequence */ + while(firstRun<runCount && levels[runs[firstRun].logicalStart]<maxLevel) { + ++firstRun; + } + if(firstRun>=runCount) { + break; /* no more such runs */ + } + + /* look for the limit run of such a sequence (the run behind it) */ + for(limitRun=firstRun; ++limitRun<runCount && levels[runs[limitRun].logicalStart]>=maxLevel;) {} + + /* Swap the entire sequence of runs from firstRun to limitRun-1. */ + endRun=limitRun-1; + while(firstRun<endRun) { + tempRun = runs[firstRun]; + runs[firstRun]=runs[endRun]; + runs[endRun]=tempRun; + ++firstRun; + --endRun; + } + + if(limitRun==runCount) { + break; /* no more such runs */ + } else { + firstRun=limitRun+1; + } + } + } + + /* now do maxLevel==old minLevel (==odd!), see above */ + if(!(minLevel&1)) { + firstRun=0; + + /* include the trailing WS run in this complete reordering */ + if(pBiDi->trailingWSStart==pBiDi->length) { + --runCount; + } + + /* Swap the entire sequence of all runs. (endRun==runCount) */ + while(firstRun<runCount) { + tempRun=runs[firstRun]; + runs[firstRun]=runs[runCount]; + runs[runCount]=tempRun; + ++firstRun; + --runCount; + } + } +} + +/* compute the runs array --------------------------------------------------- */ + +static int32_t getRunFromLogicalIndex(UBiDi *pBiDi, int32_t logicalIndex) { + Run *runs=pBiDi->runs; + int32_t runCount=pBiDi->runCount, visualStart=0, i, length, logicalStart; + + for(i=0; i<runCount; i++) { + length=runs[i].visualLimit-visualStart; + logicalStart=GET_INDEX(runs[i].logicalStart); + if((logicalIndex>=logicalStart) && (logicalIndex<(logicalStart+length))) { + return i; + } + visualStart+=length; + } + /* we should never get here */ + UPRV_UNREACHABLE_EXIT; +} + +/* + * Compute the runs array from the levels array. + * After ubidi_getRuns() returns true, runCount is guaranteed to be >0 + * and the runs are reordered. + * Odd-level runs have visualStart on their visual right edge and + * they progress visually to the left. + * If option UBIDI_OPTION_INSERT_MARKS is set, insertRemove will contain the + * sum of appropriate LRM/RLM_BEFORE/AFTER flags. + * If option UBIDI_OPTION_REMOVE_CONTROLS is set, insertRemove will contain the + * negative number of BiDi control characters within this run. + */ +U_CFUNC UBool +ubidi_getRuns(UBiDi *pBiDi, UErrorCode*) { + /* + * This method returns immediately if the runs are already set. This + * includes the case of length==0 (handled in setPara).. + */ + if (pBiDi->runCount>=0) { + return true; + } + + if(pBiDi->direction!=UBIDI_MIXED) { + /* simple, single-run case - this covers length==0 */ + /* pBiDi->paraLevel is ok even for contextual multiple paragraphs */ + getSingleRun(pBiDi, pBiDi->paraLevel); + } else /* UBIDI_MIXED, length>0 */ { + /* mixed directionality */ + int32_t length=pBiDi->length, limit; + UBiDiLevel *levels=pBiDi->levels; + int32_t i, runCount; + UBiDiLevel level=UBIDI_DEFAULT_LTR; /* initialize with no valid level */ + /* + * If there are WS characters at the end of the line + * and the run preceding them has a level different from + * paraLevel, then they will form their own run at paraLevel (L1). + * Count them separately. + * We need some special treatment for this in order to not + * modify the levels array which a line UBiDi object shares + * with its paragraph parent and its other line siblings. + * In other words, for the trailing WS, it may be + * levels[]!=paraLevel but we have to treat it like it were so. + */ + limit=pBiDi->trailingWSStart; + /* count the runs, there is at least one non-WS run, and limit>0 */ + runCount=0; + for(i=0; i<limit; ++i) { + /* increment runCount at the start of each run */ + if(levels[i]!=level) { + ++runCount; + level=levels[i]; + } + } + + /* + * We don't need to see if the last run can be merged with a trailing + * WS run because setTrailingWSStart() would have done that. + */ + if(runCount==1 && limit==length) { + /* There is only one non-WS run and no trailing WS-run. */ + getSingleRun(pBiDi, levels[0]); + } else /* runCount>1 || limit<length */ { + /* allocate and set the runs */ + Run *runs; + int32_t runIndex, start; + UBiDiLevel minLevel=UBIDI_MAX_EXPLICIT_LEVEL+1, maxLevel=0; + + /* now, count a (non-mergeable) WS run */ + if(limit<length) { + ++runCount; + } + + /* runCount>1 */ + if(getRunsMemory(pBiDi, runCount)) { + runs=pBiDi->runsMemory; + } else { + return false; + } + + /* set the runs */ + /* FOOD FOR THOUGHT: this could be optimized, e.g.: + * 464->444, 484->444, 575->555, 595->555 + * However, that would take longer. Check also how it would + * interact with BiDi control removal and inserting Marks. + */ + runIndex=0; + + /* search for the run limits and initialize visualLimit values with the run lengths */ + i=0; + do { + /* prepare this run */ + start=i; + level=levels[i]; + if(level<minLevel) { + minLevel=level; + } + if(level>maxLevel) { + maxLevel=level; + } + + /* look for the run limit */ + while(++i<limit && levels[i]==level) {} + + /* i is another run limit */ + runs[runIndex].logicalStart=start; + runs[runIndex].visualLimit=i-start; + runs[runIndex].insertRemove=0; + ++runIndex; + } while(i<limit); + + if(limit<length) { + /* there is a separate WS run */ + runs[runIndex].logicalStart=limit; + runs[runIndex].visualLimit=length-limit; + /* For the trailing WS run, pBiDi->paraLevel is ok even + if contextual multiple paragraphs. */ + if(pBiDi->paraLevel<minLevel) { + minLevel=pBiDi->paraLevel; + } + } + + /* set the object fields */ + pBiDi->runs=runs; + pBiDi->runCount=runCount; + + reorderLine(pBiDi, minLevel, maxLevel); + + /* now add the direction flags and adjust the visualLimit's to be just that */ + /* this loop will also handle the trailing WS run */ + limit=0; + for(i=0; i<runCount; ++i) { + ADD_ODD_BIT_FROM_LEVEL(runs[i].logicalStart, levels[runs[i].logicalStart]); + limit+=runs[i].visualLimit; + runs[i].visualLimit=limit; + } + + /* Set the "odd" bit for the trailing WS run. */ + /* For a RTL paragraph, it will be the *first* run in visual order. */ + /* For the trailing WS run, pBiDi->paraLevel is ok even if + contextual multiple paragraphs. */ + if(runIndex<runCount) { + int32_t trailingRun = ((pBiDi->paraLevel & 1) != 0)? 0 : runIndex; + + ADD_ODD_BIT_FROM_LEVEL(runs[trailingRun].logicalStart, pBiDi->paraLevel); + } + } + } + + /* handle insert LRM/RLM BEFORE/AFTER run */ + if(pBiDi->insertPoints.size>0) { + Point *point, *start=pBiDi->insertPoints.points, + *limit=start+pBiDi->insertPoints.size; + int32_t runIndex; + for(point=start; point<limit; point++) { + runIndex=getRunFromLogicalIndex(pBiDi, point->pos); + pBiDi->runs[runIndex].insertRemove|=point->flag; + } + } + + /* handle remove BiDi control characters */ + if(pBiDi->controlCount>0) { + int32_t runIndex; + const char16_t *start=pBiDi->text, *limit=start+pBiDi->length, *pu; + for(pu=start; pu<limit; pu++) { + if(IS_BIDI_CONTROL_CHAR(*pu)) { + runIndex=getRunFromLogicalIndex(pBiDi, (int32_t)(pu-start)); + pBiDi->runs[runIndex].insertRemove--; + } + } + } + + return true; +} + +static UBool +prepareReorder(const UBiDiLevel *levels, int32_t length, + int32_t *indexMap, + UBiDiLevel *pMinLevel, UBiDiLevel *pMaxLevel) { + int32_t start; + UBiDiLevel level, minLevel, maxLevel; + + if(levels==nullptr || length<=0) { + return false; + } + + /* determine minLevel and maxLevel */ + minLevel=UBIDI_MAX_EXPLICIT_LEVEL+1; + maxLevel=0; + for(start=length; start>0;) { + level=levels[--start]; + if(level>UBIDI_MAX_EXPLICIT_LEVEL+1) { + return false; + } + if(level<minLevel) { + minLevel=level; + } + if(level>maxLevel) { + maxLevel=level; + } + } + *pMinLevel=minLevel; + *pMaxLevel=maxLevel; + + /* initialize the index map */ + for(start=length; start>0;) { + --start; + indexMap[start]=start; + } + + return true; +} + +/* reorder a line based on a levels array (L2) ------------------------------ */ + +U_CAPI void U_EXPORT2 +ubidi_reorderLogical(const UBiDiLevel *levels, int32_t length, int32_t *indexMap) { + int32_t start, limit, sumOfSosEos; + UBiDiLevel minLevel = 0, maxLevel = 0; + + if(indexMap==nullptr || !prepareReorder(levels, length, indexMap, &minLevel, &maxLevel)) { + return; + } + + /* nothing to do? */ + if(minLevel==maxLevel && (minLevel&1)==0) { + return; + } + + /* reorder only down to the lowest odd level */ + minLevel|=1; + + /* loop maxLevel..minLevel */ + do { + start=0; + + /* loop for all sequences of levels to reorder at the current maxLevel */ + for(;;) { + /* look for a sequence of levels that are all at >=maxLevel */ + /* look for the first index of such a sequence */ + while(start<length && levels[start]<maxLevel) { + ++start; + } + if(start>=length) { + break; /* no more such sequences */ + } + + /* look for the limit of such a sequence (the index behind it) */ + for(limit=start; ++limit<length && levels[limit]>=maxLevel;) {} + + /* + * sos=start of sequence, eos=end of sequence + * + * The closed (inclusive) interval from sos to eos includes all the logical + * and visual indexes within this sequence. They are logically and + * visually contiguous and in the same range. + * + * For each run, the new visual index=sos+eos-old visual index; + * we pre-add sos+eos into sumOfSosEos -> + * new visual index=sumOfSosEos-old visual index; + */ + sumOfSosEos=start+limit-1; + + /* reorder each index in the sequence */ + do { + indexMap[start]=sumOfSosEos-indexMap[start]; + } while(++start<limit); + + /* start==limit */ + if(limit==length) { + break; /* no more such sequences */ + } else { + start=limit+1; + } + } + } while(--maxLevel>=minLevel); +} + +U_CAPI void U_EXPORT2 +ubidi_reorderVisual(const UBiDiLevel *levels, int32_t length, int32_t *indexMap) { + int32_t start, end, limit, temp; + UBiDiLevel minLevel = 0, maxLevel = 0; + + if(indexMap==nullptr || !prepareReorder(levels, length, indexMap, &minLevel, &maxLevel)) { + return; + } + + /* nothing to do? */ + if(minLevel==maxLevel && (minLevel&1)==0) { + return; + } + + /* reorder only down to the lowest odd level */ + minLevel|=1; + + /* loop maxLevel..minLevel */ + do { + start=0; + + /* loop for all sequences of levels to reorder at the current maxLevel */ + for(;;) { + /* look for a sequence of levels that are all at >=maxLevel */ + /* look for the first index of such a sequence */ + while(start<length && levels[start]<maxLevel) { + ++start; + } + if(start>=length) { + break; /* no more such runs */ + } + + /* look for the limit of such a sequence (the index behind it) */ + for(limit=start; ++limit<length && levels[limit]>=maxLevel;) {} + + /* + * Swap the entire interval of indexes from start to limit-1. + * We don't need to swap the levels for the purpose of this + * algorithm: the sequence of levels that we look at does not + * move anyway. + */ + end=limit-1; + while(start<end) { + temp=indexMap[start]; + indexMap[start]=indexMap[end]; + indexMap[end]=temp; + + ++start; + --end; + } + + if(limit==length) { + break; /* no more such sequences */ + } else { + start=limit+1; + } + } + } while(--maxLevel>=minLevel); +} + +/* API functions for logical<->visual mapping ------------------------------- */ + +U_CAPI int32_t U_EXPORT2 +ubidi_getVisualIndex(UBiDi *pBiDi, int32_t logicalIndex, UErrorCode *pErrorCode) { + int32_t visualIndex=UBIDI_MAP_NOWHERE; + RETURN_IF_NULL_OR_FAILING_ERRCODE(pErrorCode, -1); + RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, *pErrorCode, -1); + RETURN_IF_BAD_RANGE(logicalIndex, 0, pBiDi->length, *pErrorCode, -1); + + /* we can do the trivial cases without the runs array */ + switch(pBiDi->direction) { + case UBIDI_LTR: + visualIndex=logicalIndex; + break; + case UBIDI_RTL: + visualIndex=pBiDi->length-logicalIndex-1; + break; + default: + if(!ubidi_getRuns(pBiDi, pErrorCode)) { + *pErrorCode=U_MEMORY_ALLOCATION_ERROR; + return -1; + } else { + Run *runs=pBiDi->runs; + int32_t i, visualStart=0, offset, length; + + /* linear search for the run, search on the visual runs */ + for(i=0; i<pBiDi->runCount; ++i) { + length=runs[i].visualLimit-visualStart; + offset=logicalIndex-GET_INDEX(runs[i].logicalStart); + if(offset>=0 && offset<length) { + if(IS_EVEN_RUN(runs[i].logicalStart)) { + /* LTR */ + visualIndex=visualStart+offset; + } else { + /* RTL */ + visualIndex=visualStart+length-offset-1; + } + break; /* exit for loop */ + } + visualStart+=length; + } + if(i>=pBiDi->runCount) { + return UBIDI_MAP_NOWHERE; + } + } + } + + if(pBiDi->insertPoints.size>0) { + /* add the number of added marks until the calculated visual index */ + Run *runs=pBiDi->runs; + int32_t i, length, insertRemove; + int32_t visualStart=0, markFound=0; + for(i=0; ; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + if(insertRemove & (LRM_BEFORE|RLM_BEFORE)) { + markFound++; + } + /* is it the run containing the visual index? */ + if(visualIndex<runs[i].visualLimit) { + return visualIndex+markFound; + } + if(insertRemove & (LRM_AFTER|RLM_AFTER)) { + markFound++; + } + } + } + else if(pBiDi->controlCount>0) { + /* subtract the number of controls until the calculated visual index */ + Run *runs=pBiDi->runs; + int32_t i, j, start, limit, length, insertRemove; + int32_t visualStart=0, controlFound=0; + char16_t uchar=pBiDi->text[logicalIndex]; + /* is the logical index pointing to a control ? */ + if(IS_BIDI_CONTROL_CHAR(uchar)) { + return UBIDI_MAP_NOWHERE; + } + /* loop on runs */ + for(i=0; ; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + /* calculated visual index is beyond this run? */ + if(visualIndex>=runs[i].visualLimit) { + controlFound-=insertRemove; + continue; + } + /* calculated visual index must be within current run */ + if(insertRemove==0) { + return visualIndex-controlFound; + } + if(IS_EVEN_RUN(runs[i].logicalStart)) { + /* LTR: check from run start to logical index */ + start=runs[i].logicalStart; + limit=logicalIndex; + } else { + /* RTL: check from logical index to run end */ + start=logicalIndex+1; + limit=GET_INDEX(runs[i].logicalStart)+length; + } + for(j=start; j<limit; j++) { + uchar=pBiDi->text[j]; + if(IS_BIDI_CONTROL_CHAR(uchar)) { + controlFound++; + } + } + return visualIndex-controlFound; + } + } + + return visualIndex; +} + +U_CAPI int32_t U_EXPORT2 +ubidi_getLogicalIndex(UBiDi *pBiDi, int32_t visualIndex, UErrorCode *pErrorCode) { + Run *runs; + int32_t i, runCount, start; + RETURN_IF_NULL_OR_FAILING_ERRCODE(pErrorCode, -1); + RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, *pErrorCode, -1); + RETURN_IF_BAD_RANGE(visualIndex, 0, pBiDi->resultLength, *pErrorCode, -1); + /* we can do the trivial cases without the runs array */ + if(pBiDi->insertPoints.size==0 && pBiDi->controlCount==0) { + if(pBiDi->direction==UBIDI_LTR) { + return visualIndex; + } + else if(pBiDi->direction==UBIDI_RTL) { + return pBiDi->length-visualIndex-1; + } + } + if(!ubidi_getRuns(pBiDi, pErrorCode)) { + *pErrorCode=U_MEMORY_ALLOCATION_ERROR; + return -1; + } + + runs=pBiDi->runs; + runCount=pBiDi->runCount; + if(pBiDi->insertPoints.size>0) { + /* handle inserted LRM/RLM */ + int32_t markFound=0, insertRemove; + int32_t visualStart=0, length; + runs=pBiDi->runs; + /* subtract number of marks until visual index */ + for(i=0; ; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + if(insertRemove&(LRM_BEFORE|RLM_BEFORE)) { + if(visualIndex<=(visualStart+markFound)) { + return UBIDI_MAP_NOWHERE; + } + markFound++; + } + /* is adjusted visual index within this run? */ + if(visualIndex<(runs[i].visualLimit+markFound)) { + visualIndex-=markFound; + break; + } + if(insertRemove&(LRM_AFTER|RLM_AFTER)) { + if(visualIndex==(visualStart+length+markFound)) { + return UBIDI_MAP_NOWHERE; + } + markFound++; + } + } + } + else if(pBiDi->controlCount>0) { + /* handle removed BiDi control characters */ + int32_t controlFound=0, insertRemove, length; + int32_t logicalStart, logicalEnd, visualStart=0, j, k; + char16_t uchar; + UBool evenRun; + /* add number of controls until visual index */ + for(i=0; ; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + /* is adjusted visual index beyond current run? */ + if(visualIndex>=(runs[i].visualLimit-controlFound+insertRemove)) { + controlFound-=insertRemove; + continue; + } + /* adjusted visual index is within current run */ + if(insertRemove==0) { + visualIndex+=controlFound; + break; + } + /* count non-control chars until visualIndex */ + logicalStart=runs[i].logicalStart; + evenRun=IS_EVEN_RUN(logicalStart); + REMOVE_ODD_BIT(logicalStart); + logicalEnd=logicalStart+length-1; + for(j=0; j<length; j++) { + k= evenRun ? logicalStart+j : logicalEnd-j; + uchar=pBiDi->text[k]; + if(IS_BIDI_CONTROL_CHAR(uchar)) { + controlFound++; + } + if((visualIndex+controlFound)==(visualStart+j)) { + break; + } + } + visualIndex+=controlFound; + break; + } + } + /* handle all cases */ + if(runCount<=10) { + /* linear search for the run */ + for(i=0; visualIndex>=runs[i].visualLimit; ++i) {} + } else { + /* binary search for the run */ + int32_t begin=0, limit=runCount; + + /* the middle if() is guaranteed to find the run, we don't need a loop limit */ + for(;;) { + i=(begin+limit)/2; + if(visualIndex>=runs[i].visualLimit) { + begin=i+1; + } else if(i==0 || visualIndex>=runs[i-1].visualLimit) { + break; + } else { + limit=i; + } + } + } + + start=runs[i].logicalStart; + if(IS_EVEN_RUN(start)) { + /* LTR */ + /* the offset in runs[i] is visualIndex-runs[i-1].visualLimit */ + if(i>0) { + visualIndex-=runs[i-1].visualLimit; + } + return start+visualIndex; + } else { + /* RTL */ + return GET_INDEX(start)+runs[i].visualLimit-visualIndex-1; + } +} + +U_CAPI void U_EXPORT2 +ubidi_getLogicalMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode) { + RETURN_VOID_IF_NULL_OR_FAILING_ERRCODE(pErrorCode); + /* ubidi_countRuns() checks for VALID_PARA_OR_LINE */ + ubidi_countRuns(pBiDi, pErrorCode); + if(U_FAILURE(*pErrorCode)) { + /* no op */ + } else if(indexMap==nullptr) { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + } else { + /* fill a logical-to-visual index map using the runs[] */ + int32_t visualStart, visualLimit, i, j, k; + int32_t logicalStart, logicalLimit; + Run *runs=pBiDi->runs; + if (pBiDi->length<=0) { + return; + } + if (pBiDi->length>pBiDi->resultLength) { + uprv_memset(indexMap, 0xFF, pBiDi->length*sizeof(int32_t)); + } + + visualStart=0; + for(j=0; j<pBiDi->runCount; ++j) { + logicalStart=GET_INDEX(runs[j].logicalStart); + visualLimit=runs[j].visualLimit; + if(IS_EVEN_RUN(runs[j].logicalStart)) { + do { /* LTR */ + indexMap[logicalStart++]=visualStart++; + } while(visualStart<visualLimit); + } else { + logicalStart+=visualLimit-visualStart; /* logicalLimit */ + do { /* RTL */ + indexMap[--logicalStart]=visualStart++; + } while(visualStart<visualLimit); + } + /* visualStart==visualLimit; */ + } + + if(pBiDi->insertPoints.size>0) { + int32_t markFound=0, runCount=pBiDi->runCount; + int32_t length, insertRemove; + visualStart=0; + /* add number of marks found until each index */ + for(i=0; i<runCount; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + if(insertRemove&(LRM_BEFORE|RLM_BEFORE)) { + markFound++; + } + if(markFound>0) { + logicalStart=GET_INDEX(runs[i].logicalStart); + logicalLimit=logicalStart+length; + for(j=logicalStart; j<logicalLimit; j++) { + indexMap[j]+=markFound; + } + } + if(insertRemove&(LRM_AFTER|RLM_AFTER)) { + markFound++; + } + } + } + else if(pBiDi->controlCount>0) { + int32_t controlFound=0, runCount=pBiDi->runCount; + int32_t length, insertRemove; + UBool evenRun; + char16_t uchar; + visualStart=0; + /* subtract number of controls found until each index */ + for(i=0; i<runCount; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + /* no control found within previous runs nor within this run */ + if((controlFound-insertRemove)==0) { + continue; + } + logicalStart=runs[i].logicalStart; + evenRun=IS_EVEN_RUN(logicalStart); + REMOVE_ODD_BIT(logicalStart); + logicalLimit=logicalStart+length; + /* if no control within this run */ + if(insertRemove==0) { + for(j=logicalStart; j<logicalLimit; j++) { + indexMap[j]-=controlFound; + } + continue; + } + for(j=0; j<length; j++) { + k= evenRun ? logicalStart+j : logicalLimit-j-1; + uchar=pBiDi->text[k]; + if(IS_BIDI_CONTROL_CHAR(uchar)) { + controlFound++; + indexMap[k]=UBIDI_MAP_NOWHERE; + continue; + } + indexMap[k]-=controlFound; + } + } + } + } +} + +U_CAPI void U_EXPORT2 +ubidi_getVisualMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode) { + RETURN_VOID_IF_NULL_OR_FAILING_ERRCODE(pErrorCode); + if(indexMap==nullptr) { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return; + } + /* ubidi_countRuns() checks for VALID_PARA_OR_LINE */ + ubidi_countRuns(pBiDi, pErrorCode); + if(U_SUCCESS(*pErrorCode)) { + /* fill a visual-to-logical index map using the runs[] */ + Run *runs=pBiDi->runs, *runsLimit=runs+pBiDi->runCount; + int32_t logicalStart, visualStart, visualLimit, *pi=indexMap; + + if (pBiDi->resultLength<=0) { + return; + } + visualStart=0; + for(; runs<runsLimit; ++runs) { + logicalStart=runs->logicalStart; + visualLimit=runs->visualLimit; + if(IS_EVEN_RUN(logicalStart)) { + do { /* LTR */ + *pi++ = logicalStart++; + } while(++visualStart<visualLimit); + } else { + REMOVE_ODD_BIT(logicalStart); + logicalStart+=visualLimit-visualStart; /* logicalLimit */ + do { /* RTL */ + *pi++ = --logicalStart; + } while(++visualStart<visualLimit); + } + /* visualStart==visualLimit; */ + } + + if(pBiDi->insertPoints.size>0) { + int32_t markFound=0, runCount=pBiDi->runCount; + int32_t insertRemove, i, j, k; + runs=pBiDi->runs; + /* count all inserted marks */ + for(i=0; i<runCount; i++) { + insertRemove=runs[i].insertRemove; + if(insertRemove&(LRM_BEFORE|RLM_BEFORE)) { + markFound++; + } + if(insertRemove&(LRM_AFTER|RLM_AFTER)) { + markFound++; + } + } + /* move back indexes by number of preceding marks */ + k=pBiDi->resultLength; + for(i=runCount-1; i>=0 && markFound>0; i--) { + insertRemove=runs[i].insertRemove; + if(insertRemove&(LRM_AFTER|RLM_AFTER)) { + indexMap[--k]= UBIDI_MAP_NOWHERE; + markFound--; + } + visualStart= i>0 ? runs[i-1].visualLimit : 0; + for(j=runs[i].visualLimit-1; j>=visualStart && markFound>0; j--) { + indexMap[--k]=indexMap[j]; + } + if(insertRemove&(LRM_BEFORE|RLM_BEFORE)) { + indexMap[--k]= UBIDI_MAP_NOWHERE; + markFound--; + } + } + } + else if(pBiDi->controlCount>0) { + int32_t runCount=pBiDi->runCount, logicalEnd; + int32_t insertRemove, length, i, j, k, m; + char16_t uchar; + UBool evenRun; + runs=pBiDi->runs; + visualStart=0; + /* move forward indexes by number of preceding controls */ + k=0; + for(i=0; i<runCount; i++, visualStart+=length) { + length=runs[i].visualLimit-visualStart; + insertRemove=runs[i].insertRemove; + /* if no control found yet, nothing to do in this run */ + if((insertRemove==0)&&(k==visualStart)) { + k+=length; + continue; + } + /* if no control in this run */ + if(insertRemove==0) { + visualLimit=runs[i].visualLimit; + for(j=visualStart; j<visualLimit; j++) { + indexMap[k++]=indexMap[j]; + } + continue; + } + logicalStart=runs[i].logicalStart; + evenRun=IS_EVEN_RUN(logicalStart); + REMOVE_ODD_BIT(logicalStart); + logicalEnd=logicalStart+length-1; + for(j=0; j<length; j++) { + m= evenRun ? logicalStart+j : logicalEnd-j; + uchar=pBiDi->text[m]; + if(!IS_BIDI_CONTROL_CHAR(uchar)) { + indexMap[k++]=m; + } + } + } + } + } +} + +U_CAPI void U_EXPORT2 +ubidi_invertMap(const int32_t *srcMap, int32_t *destMap, int32_t length) { + if(srcMap!=nullptr && destMap!=nullptr && length>0) { + const int32_t *pi; + int32_t destLength=-1, count=0; + /* find highest value and count positive indexes in srcMap */ + pi=srcMap+length; + while(pi>srcMap) { + if(*--pi>destLength) { + destLength=*pi; + } + if(*pi>=0) { + count++; + } + } + destLength++; /* add 1 for origin 0 */ + if(count<destLength) { + /* we must fill unmatched destMap entries with -1 */ + uprv_memset(destMap, 0xFF, destLength*sizeof(int32_t)); + } + pi=srcMap+length; + while(length>0) { + if(*--pi>=0) { + destMap[*pi]=--length; + } else { + --length; + } + } + } +} |