U_CAPI const UBiDiLevel * U_EXPORT2
ubidi_getLevels(UBiDi *pBiDi, UErrorCode *pErrorCode) {
int32_t start, length;
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return NULL;
} else if(pBiDi==NULL || (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) {
icu_memcpy(levels, pBiDi->levels, start);
}
icu_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_setPara(UBiDi *pBiDi, const UChar *text, int32_t length,
UBiDiLevel paraLevel, UBiDiLevel *embeddingLevels,
UErrorCode *pErrorCode) {
UBiDiDirection direction;
/* check the argument values */
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return;
} else if(pBiDi==NULL || text==NULL ||
((UBIDI_MAX_EXPLICIT_LEVEL<paraLevel) && !IS_DEFAULT_LEVEL(paraLevel)) ||
length<-1
) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return;
}
if(length==-1) {
// length=u_strlen(text);
const UChar *p = text - 1;
while(*++p);
length = p - text;
}
/* initialize the UBiDi structure */
pBiDi->text=text;
pBiDi->length=length;
pBiDi->paraLevel=paraLevel;
pBiDi->direction=UBIDI_LTR;
pBiDi->trailingWSStart=length; /* the levels[] will reflect the WS run */
pBiDi->dirProps=NULL;
pBiDi->levels=NULL;
pBiDi->runs=NULL;
if(length==0) {
/*
* For an empty paragraph, create a UBiDi object with the paraLevel and
* the flags and the direction set but without allocating zero-length arrays.
* There is nothing more to do.
*/
if(IS_DEFAULT_LEVEL(paraLevel)) {
pBiDi->paraLevel&=1;
}
if(paraLevel&1) {
pBiDi->flags=DIRPROP_FLAG(R);
pBiDi->direction=UBIDI_RTL;
} else {
pBiDi->flags=DIRPROP_FLAG(L);
pBiDi->direction=UBIDI_LTR;
}
pBiDi->runCount=0;
return;
}
pBiDi->runCount=-1;
/*
* Get the directional properties,
* the flags bit-set, and
* determine the partagraph level if necessary.
*/
if(getDirPropsMemory(pBiDi, length)) {
pBiDi->dirProps=pBiDi->dirPropsMemory;
getDirProps(pBiDi, text);
} else {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return;
}
if (getLevelsMemory(pBiDi, length)) {
pBiDi->levels=pBiDi->levelsMemory;
/* are explicit levels specified? */
if(embeddingLevels==NULL) {
/* no: determine explicit levels according to the (Xn) rules */
direction=resolveExplicitLevels(pBiDi);
} else {
/* set BN for all explicit codes, check that all levels are paraLevel..UBIDI_MAX_EXPLICIT_LEVEL */
icu_memcpy(pBiDi->levels, embeddingLevels, length);
direction=checkExplicitLevels(pBiDi, pErrorCode);
if(U_FAILURE(*pErrorCode)) {
return;
}
}
} else {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return;
}
/*
* The steps after (X9) in the UBiDi algorithm are performed only if
* the paragraph text has mixed directionality!
*/
pBiDi->direction=direction;
switch(direction) {
case UBIDI_LTR:
/* make sure paraLevel is even */
pBiDi->paraLevel=(UBiDiLevel)((pBiDi->paraLevel+1)&~1);
/* all levels are implicitly at paraLevel (important for ubidi_getLevels()) */
pBiDi->trailingWSStart=0;
break;
case UBIDI_RTL:
/* make sure paraLevel is odd */
pBiDi->paraLevel|=1;
/* all levels are implicitly at paraLevel (important for ubidi_getLevels()) */
pBiDi->trailingWSStart=0;
break;
default:
/*
* If there are no external levels specified and there
* are no significant explicit level codes in the text,
* then we can treat the entire paragraph as one run.
* Otherwise, we need to perform the following rules on runs of
* the text with the same embedding levels. (X10)
* "Significant" explicit level codes are ones that actually
* affect non-BN characters.
* Examples for "insignificant" ones are empty embeddings
* LRE-PDF, LRE-RLE-PDF-PDF, etc.
*/
if(embeddingLevels==NULL && !(pBiDi->flags&DIRPROP_FLAG_MULTI_RUNS)) {
resolveImplicitLevels(pBiDi, 0, length,
GET_LR_FROM_LEVEL(pBiDi->paraLevel),
GET_LR_FROM_LEVEL(pBiDi->paraLevel));
} else {
/* sor, eor: start and end types of same-level-run */
UBiDiLevel *levels=pBiDi->levels;
int32_t start, limit=0;
UBiDiLevel level, nextLevel;
DirProp sor, eor;
/* determine the first sor and set eor to it because of the loop body (sor=eor there) */
level=pBiDi->paraLevel;
nextLevel=levels[0];
if(level<nextLevel) {
eor=GET_LR_FROM_LEVEL(nextLevel);
} else {
eor=GET_LR_FROM_LEVEL(level);
}
do {
/* determine start and limit of the run (end points just behind the run) */
/* the values for this run's start are the same as for the previous run's end */
sor=eor;
start=limit;
level=nextLevel;
/* search for the limit of this run */
while(++limit<length && levels[limit]==level) {}
/* get the correct level of the next run */
if(limit<length) {
nextLevel=levels[limit];
} else {
nextLevel=pBiDi->paraLevel;
}
/* determine eor from max(level, nextLevel); sor is last run's eor */
if((level&~UBIDI_LEVEL_OVERRIDE)<(nextLevel&~UBIDI_LEVEL_OVERRIDE)) {
eor=GET_LR_FROM_LEVEL(nextLevel);
} else {
eor=GET_LR_FROM_LEVEL(level);
}
/* if the run consists of overridden directional types, then there
are no implicit types to be resolved */
if(!(level&UBIDI_LEVEL_OVERRIDE)) {
resolveImplicitLevels(pBiDi, start, limit, sor, eor);
} else {
/* remove the UBIDI_LEVEL_OVERRIDE flags */
do {
levels[start++]&=~UBIDI_LEVEL_OVERRIDE;
} while(start<limit);
}
} while(limit<length);
}
/* reset the embedding levels for some non-graphic characters (L1), (X9) */
adjustWSLevels(pBiDi);
/* for "inverse BiDi", ubidi_getRuns() modifies the levels of numeric runs following RTL runs */
if(pBiDi->isInverse) {
if(!ubidi_getRuns(pBiDi)) {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return;
}
}
break;
}
}
