/*
******************************************************************************
*
* Copyright (C) 1999-2009, 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+=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;
}
}
}
}