/* ****************************************************************************** * * Copyright (C) 1999-2010, International Business Machines * Corporation and others. All Rights Reserved. * ****************************************************************************** * file name: ubidiln.c * encoding: US-ASCII * 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 3.0 BiDi algorithm as defined in * http://www.unicode.org/unicode/reports/tr9/ , version 13, * also described in The Unicode Standard, Version 4.0.1 . * * 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==NULL. * * 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(NO_CONTEXT_RTL(dirProps[start-1])==B) { pBiDi->trailingWSStart=start; /* currently == pBiDi->length */ return; } /* go backwards across all WS, BN, explicit codes */ while(start>0 && DIRPROP_FLAG_NC(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==NULL) { *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; return; } if(ubidi_getParagraph(pParaBiDi, start, NULL, NULL, NULL, pErrorCode) != ubidi_getParagraph(pParaBiDi, limit-1, NULL, NULL, NULL, pErrorCode)) { /* the line crosses a paragraph boundary */ *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; return; } /* set the values in pLineBiDi from its pParaBiDi parent */ pLineBiDi->pParaBiDi=NULL; /* 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=NULL; 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, NULL); RETURN_IF_NOT_VALID_PARA_OR_LINE(pBiDi, *pErrorCode, NULL); if((length=pBiDi->length)<=0) { *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; return NULL; } 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 NULL; } } 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!=NULL) { *pLogicalStart=GET_INDEX(start); } if(pLength!=NULL) { 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, UErrorCode *pErrorCode) { 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 */ U_ASSERT(FALSE); *pErrorCode = U_INVALID_STATE_ERROR; return 0; } /* * 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 *pErrorCode) { /* * 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, pErrorCode); pBiDi->runs[runIndex].insertRemove|=point->flag; } } /* handle remove BiDi control characters */ if(pBiDi->controlCount>0) { int32_t runIndex; const UChar *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), pErrorCode); 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==NULL || 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==NULL || !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==NULL || !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; UChar 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; UChar 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==NULL) { *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; UChar 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==NULL) { *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; UChar 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!=NULL && destMap!=NULL && 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; } } } }