diff options
Diffstat (limited to 'thirdparty/icu4c/common/ubidiwrt.cpp')
-rw-r--r-- | thirdparty/icu4c/common/ubidiwrt.cpp | 650 |
1 files changed, 650 insertions, 0 deletions
diff --git a/thirdparty/icu4c/common/ubidiwrt.cpp b/thirdparty/icu4c/common/ubidiwrt.cpp new file mode 100644 index 0000000000..a69c0a4b8b --- /dev/null +++ b/thirdparty/icu4c/common/ubidiwrt.cpp @@ -0,0 +1,650 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +****************************************************************************** +* +* Copyright (C) 2000-2015, International Business Machines +* Corporation and others. All Rights Reserved. +* +****************************************************************************** +* file name: ubidiwrt.c +* encoding: UTF-8 +* tab size: 8 (not used) +* indentation:4 +* +* created on: 1999aug06 +* created by: Markus W. Scherer, updated by Matitiahu Allouche +* +* This file contains implementations for BiDi functions that use +* the core algorithm and core API to write reordered text. +*/ + +#include "unicode/utypes.h" +#include "unicode/ustring.h" +#include "unicode/uchar.h" +#include "unicode/ubidi.h" +#include "unicode/utf16.h" +#include "cmemory.h" +#include "ustr_imp.h" +#include "ubidiimp.h" + +/* + * The function implementations in this file are designed + * for UTF-16 and UTF-32, not for UTF-8. + * + * Assumptions that are not true for UTF-8: + * - Any code point always needs the same number of code units + * ("minimum-length-problem" of UTF-8) + * - The BiDi control characters need only one code unit each + * + * Further assumptions for all UTFs: + * - u_charMirror(c) needs the same number of code units as c + */ +#if defined(UTF_SIZE) && UTF_SIZE==8 +# error reimplement ubidi_writeReordered() for UTF-8, see comment above +#endif + +#define IS_COMBINING(type) ((1UL<<(type))&(1UL<<U_NON_SPACING_MARK|1UL<<U_COMBINING_SPACING_MARK|1UL<<U_ENCLOSING_MARK)) + +/* + * When we have UBIDI_OUTPUT_REVERSE set on ubidi_writeReordered(), then we + * semantically write RTL runs in reverse and later reverse them again. + * Instead, we actually write them in forward order to begin with. + * However, if the RTL run was to be mirrored, we need to mirror here now + * since the implicit second reversal must not do it. + * It looks strange to do mirroring in LTR output, but it is only because + * we are writing RTL output in reverse. + */ +static int32_t +doWriteForward(const UChar *src, int32_t srcLength, + UChar *dest, int32_t destSize, + uint16_t options, + UErrorCode *pErrorCode) { + /* optimize for several combinations of options */ + switch(options&(UBIDI_REMOVE_BIDI_CONTROLS|UBIDI_DO_MIRRORING)) { + case 0: { + /* simply copy the LTR run to the destination */ + int32_t length=srcLength; + if(destSize<length) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + return srcLength; + } + do { + *dest++=*src++; + } while(--length>0); + return srcLength; + } + case UBIDI_DO_MIRRORING: { + /* do mirroring */ + int32_t i=0, j=0; + UChar32 c; + + if(destSize<srcLength) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + return srcLength; + } + do { + U16_NEXT(src, i, srcLength, c); + c=u_charMirror(c); + U16_APPEND_UNSAFE(dest, j, c); + } while(i<srcLength); + return srcLength; + } + case UBIDI_REMOVE_BIDI_CONTROLS: { + /* copy the LTR run and remove any BiDi control characters */ + int32_t remaining=destSize; + UChar c; + do { + c=*src++; + if(!IS_BIDI_CONTROL_CHAR(c)) { + if(--remaining<0) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + + /* preflight the length */ + while(--srcLength>0) { + c=*src++; + if(!IS_BIDI_CONTROL_CHAR(c)) { + --remaining; + } + } + return destSize-remaining; + } + *dest++=c; + } + } while(--srcLength>0); + return destSize-remaining; + } + default: { + /* remove BiDi control characters and do mirroring */ + int32_t remaining=destSize; + int32_t i, j=0; + UChar32 c; + do { + i=0; + U16_NEXT(src, i, srcLength, c); + src+=i; + srcLength-=i; + if(!IS_BIDI_CONTROL_CHAR(c)) { + remaining-=i; + if(remaining<0) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + + /* preflight the length */ + while(srcLength>0) { + c=*src++; + if(!IS_BIDI_CONTROL_CHAR(c)) { + --remaining; + } + --srcLength; + } + return destSize-remaining; + } + c=u_charMirror(c); + U16_APPEND_UNSAFE(dest, j, c); + } + } while(srcLength>0); + return j; + } + } /* end of switch */ +} + +static int32_t +doWriteReverse(const UChar *src, int32_t srcLength, + UChar *dest, int32_t destSize, + uint16_t options, + UErrorCode *pErrorCode) { + /* + * RTL run - + * + * RTL runs need to be copied to the destination in reverse order + * of code points, not code units, to keep Unicode characters intact. + * + * The general strategy for this is to read the source text + * in backward order, collect all code units for a code point + * (and optionally following combining characters, see below), + * and copy all these code units in ascending order + * to the destination for this run. + * + * Several options request whether combining characters + * should be kept after their base characters, + * whether BiDi control characters should be removed, and + * whether characters should be replaced by their mirror-image + * equivalent Unicode characters. + */ + int32_t i, j; + UChar32 c; + + /* optimize for several combinations of options */ + switch(options&(UBIDI_REMOVE_BIDI_CONTROLS|UBIDI_DO_MIRRORING|UBIDI_KEEP_BASE_COMBINING)) { + case 0: + /* + * With none of the "complicated" options set, the destination + * run will have the same length as the source run, + * and there is no mirroring and no keeping combining characters + * with their base characters. + */ + if(destSize<srcLength) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + return srcLength; + } + destSize=srcLength; + + /* preserve character integrity */ + do { + /* i is always after the last code unit known to need to be kept in this segment */ + i=srcLength; + + /* collect code units for one base character */ + U16_BACK_1(src, 0, srcLength); + + /* copy this base character */ + j=srcLength; + do { + *dest++=src[j++]; + } while(j<i); + } while(srcLength>0); + break; + case UBIDI_KEEP_BASE_COMBINING: + /* + * Here, too, the destination + * run will have the same length as the source run, + * and there is no mirroring. + * We do need to keep combining characters with their base characters. + */ + if(destSize<srcLength) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + return srcLength; + } + destSize=srcLength; + + /* preserve character integrity */ + do { + /* i is always after the last code unit known to need to be kept in this segment */ + i=srcLength; + + /* collect code units and modifier letters for one base character */ + do { + U16_PREV(src, 0, srcLength, c); + } while(srcLength>0 && IS_COMBINING(u_charType(c))); + + /* copy this "user character" */ + j=srcLength; + do { + *dest++=src[j++]; + } while(j<i); + } while(srcLength>0); + break; + default: + /* + * With several "complicated" options set, this is the most + * general and the slowest copying of an RTL run. + * We will do mirroring, remove BiDi controls, and + * keep combining characters with their base characters + * as requested. + */ + if(!(options&UBIDI_REMOVE_BIDI_CONTROLS)) { + i=srcLength; + } else { + /* we need to find out the destination length of the run, + which will not include the BiDi control characters */ + int32_t length=srcLength; + UChar ch; + + i=0; + do { + ch=*src++; + if(!IS_BIDI_CONTROL_CHAR(ch)) { + ++i; + } + } while(--length>0); + src-=srcLength; + } + + if(destSize<i) { + *pErrorCode=U_BUFFER_OVERFLOW_ERROR; + return i; + } + destSize=i; + + /* preserve character integrity */ + do { + /* i is always after the last code unit known to need to be kept in this segment */ + i=srcLength; + + /* collect code units for one base character */ + U16_PREV(src, 0, srcLength, c); + if(options&UBIDI_KEEP_BASE_COMBINING) { + /* collect modifier letters for this base character */ + while(srcLength>0 && IS_COMBINING(u_charType(c))) { + U16_PREV(src, 0, srcLength, c); + } + } + + if(options&UBIDI_REMOVE_BIDI_CONTROLS && IS_BIDI_CONTROL_CHAR(c)) { + /* do not copy this BiDi control character */ + continue; + } + + /* copy this "user character" */ + j=srcLength; + if(options&UBIDI_DO_MIRRORING) { + /* mirror only the base character */ + int32_t k=0; + c=u_charMirror(c); + U16_APPEND_UNSAFE(dest, k, c); + dest+=k; + j+=k; + } + while(j<i) { + *dest++=src[j++]; + } + } while(srcLength>0); + break; + } /* end of switch */ + + return destSize; +} + +U_CAPI int32_t U_EXPORT2 +ubidi_writeReverse(const UChar *src, int32_t srcLength, + UChar *dest, int32_t destSize, + uint16_t options, + UErrorCode *pErrorCode) { + int32_t destLength; + + if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) { + return 0; + } + + /* more error checking */ + if( src==NULL || srcLength<-1 || + destSize<0 || (destSize>0 && dest==NULL)) + { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return 0; + } + + /* do input and output overlap? */ + if( dest!=NULL && + ((src>=dest && src<dest+destSize) || + (dest>=src && dest<src+srcLength))) + { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return 0; + } + + if(srcLength==-1) { + srcLength=u_strlen(src); + } + if(srcLength>0) { + destLength=doWriteReverse(src, srcLength, dest, destSize, options, pErrorCode); + } else { + /* nothing to do */ + destLength=0; + } + + return u_terminateUChars(dest, destSize, destLength, pErrorCode); +} + +// Ticket 20907 - The optimizer in MSVC/Visual Studio versions below 16.4 has trouble with this +// function on Windows ARM64. As a work-around, we disable optimizations for this function. +// This work-around could/should be removed once the following versions of Visual Studio are no +// longer supported: All versions of VS2017, and versions of VS2019 below 16.4. +#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924)) +#pragma optimize( "", off ) +#endif +U_CAPI int32_t U_EXPORT2 +ubidi_writeReordered(UBiDi *pBiDi, + UChar *dest, int32_t destSize, + uint16_t options, + UErrorCode *pErrorCode) { + const UChar *text; + UChar *saveDest; + int32_t length, destCapacity; + int32_t run, runCount, logicalStart, runLength; + + if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) { + return 0; + } + + /* more error checking */ + if( pBiDi==NULL || + (text=pBiDi->text)==NULL || (length=pBiDi->length)<0 || + destSize<0 || (destSize>0 && dest==NULL)) + { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return 0; + } + + /* do input and output overlap? */ + if( dest!=NULL && + ((text>=dest && text<dest+destSize) || + (dest>=text && dest<text+pBiDi->originalLength))) + { + *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR; + return 0; + } + + if(length==0) { + /* nothing to do */ + return u_terminateUChars(dest, destSize, 0, pErrorCode); + } + + runCount=ubidi_countRuns(pBiDi, pErrorCode); + if(U_FAILURE(*pErrorCode)) { + return 0; + } + + /* destSize shrinks, later destination length=destCapacity-destSize */ + saveDest=dest; + destCapacity=destSize; + + /* + * Option "insert marks" implies UBIDI_INSERT_LRM_FOR_NUMERIC if the + * reordering mode (checked below) is appropriate. + */ + if(pBiDi->reorderingOptions & UBIDI_OPTION_INSERT_MARKS) { + options|=UBIDI_INSERT_LRM_FOR_NUMERIC; + options&=~UBIDI_REMOVE_BIDI_CONTROLS; + } + /* + * Option "remove controls" implies UBIDI_REMOVE_BIDI_CONTROLS + * and cancels UBIDI_INSERT_LRM_FOR_NUMERIC. + */ + if(pBiDi->reorderingOptions & UBIDI_OPTION_REMOVE_CONTROLS) { + options|=UBIDI_REMOVE_BIDI_CONTROLS; + options&=~UBIDI_INSERT_LRM_FOR_NUMERIC; + } + /* + * If we do not perform the "inverse BiDi" algorithm, then we + * don't need to insert any LRMs, and don't need to test for it. + */ + if((pBiDi->reorderingMode != UBIDI_REORDER_INVERSE_NUMBERS_AS_L) && + (pBiDi->reorderingMode != UBIDI_REORDER_INVERSE_LIKE_DIRECT) && + (pBiDi->reorderingMode != UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL) && + (pBiDi->reorderingMode != UBIDI_REORDER_RUNS_ONLY)) { + options&=~UBIDI_INSERT_LRM_FOR_NUMERIC; + } + /* + * Iterate through all visual runs and copy the run text segments to + * the destination, according to the options. + * + * The tests for where to insert LRMs ignore the fact that there may be + * BN codes or non-BMP code points at the beginning and end of a run; + * they may insert LRMs unnecessarily but the tests are faster this way + * (this would have to be improved for UTF-8). + * + * Note that the only errors that are set by doWriteXY() are buffer overflow + * errors. Ignore them until the end, and continue for preflighting. + */ + if(!(options&UBIDI_OUTPUT_REVERSE)) { + /* forward output */ + if(!(options&UBIDI_INSERT_LRM_FOR_NUMERIC)) { + /* do not insert BiDi controls */ + for(run=0; run<runCount; ++run) { + if(UBIDI_LTR==ubidi_getVisualRun(pBiDi, run, &logicalStart, &runLength)) { + runLength=doWriteForward(text+logicalStart, runLength, + dest, destSize, + (uint16_t)(options&~UBIDI_DO_MIRRORING), pErrorCode); + } else { + runLength=doWriteReverse(text+logicalStart, runLength, + dest, destSize, + options, pErrorCode); + } + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + } + } else { + /* insert BiDi controls for "inverse BiDi" */ + const DirProp *dirProps=pBiDi->dirProps; + const UChar *src; + UChar uc; + UBiDiDirection dir; + int32_t markFlag; + + for(run=0; run<runCount; ++run) { + dir=ubidi_getVisualRun(pBiDi, run, &logicalStart, &runLength); + src=text+logicalStart; + /* check if something relevant in insertPoints */ + markFlag=pBiDi->runs[run].insertRemove; + if(markFlag<0) { /* BiDi controls count */ + markFlag=0; + } + + if(UBIDI_LTR==dir) { + if((pBiDi->isInverse) && + (/*run>0 &&*/ dirProps[logicalStart]!=L)) { + markFlag |= LRM_BEFORE; + } + if (markFlag & LRM_BEFORE) { + uc=LRM_CHAR; + } + else if (markFlag & RLM_BEFORE) { + uc=RLM_CHAR; + } + else uc=0; + if(uc) { + if(destSize>0) { + *dest++=uc; + } + --destSize; + } + + runLength=doWriteForward(src, runLength, + dest, destSize, + (uint16_t)(options&~UBIDI_DO_MIRRORING), pErrorCode); + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + + if((pBiDi->isInverse) && + (/*run<runCount-1 &&*/ dirProps[logicalStart+runLength-1]!=L)) { + markFlag |= LRM_AFTER; + } + if (markFlag & LRM_AFTER) { + uc=LRM_CHAR; + } + else if (markFlag & RLM_AFTER) { + uc=RLM_CHAR; + } + else uc=0; + if(uc) { + if(destSize>0) { + *dest++=uc; + } + --destSize; + } + } else { /* RTL run */ + if((pBiDi->isInverse) && + (/*run>0 &&*/ !(MASK_R_AL&DIRPROP_FLAG(dirProps[logicalStart+runLength-1])))) { + markFlag |= RLM_BEFORE; + } + if (markFlag & LRM_BEFORE) { + uc=LRM_CHAR; + } + else if (markFlag & RLM_BEFORE) { + uc=RLM_CHAR; + } + else uc=0; + if(uc) { + if(destSize>0) { + *dest++=uc; + } + --destSize; + } + + runLength=doWriteReverse(src, runLength, + dest, destSize, + options, pErrorCode); + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + + if((pBiDi->isInverse) && + (/*run<runCount-1 &&*/ !(MASK_R_AL&DIRPROP_FLAG(dirProps[logicalStart])))) { + markFlag |= RLM_AFTER; + } + if (markFlag & LRM_AFTER) { + uc=LRM_CHAR; + } + else if (markFlag & RLM_AFTER) { + uc=RLM_CHAR; + } + else uc=0; + if(uc) { + if(destSize>0) { + *dest++=uc; + } + --destSize; + } + } + } + } + } else { + /* reverse output */ + if(!(options&UBIDI_INSERT_LRM_FOR_NUMERIC)) { + /* do not insert BiDi controls */ + for(run=runCount; --run>=0;) { + if(UBIDI_LTR==ubidi_getVisualRun(pBiDi, run, &logicalStart, &runLength)) { + runLength=doWriteReverse(text+logicalStart, runLength, + dest, destSize, + (uint16_t)(options&~UBIDI_DO_MIRRORING), pErrorCode); + } else { + runLength=doWriteForward(text+logicalStart, runLength, + dest, destSize, + options, pErrorCode); + } + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + } + } else { + /* insert BiDi controls for "inverse BiDi" */ + const DirProp *dirProps=pBiDi->dirProps; + const UChar *src; + UBiDiDirection dir; + + for(run=runCount; --run>=0;) { + /* reverse output */ + dir=ubidi_getVisualRun(pBiDi, run, &logicalStart, &runLength); + src=text+logicalStart; + + if(UBIDI_LTR==dir) { + if(/*run<runCount-1 &&*/ dirProps[logicalStart+runLength-1]!=L) { + if(destSize>0) { + *dest++=LRM_CHAR; + } + --destSize; + } + + runLength=doWriteReverse(src, runLength, + dest, destSize, + (uint16_t)(options&~UBIDI_DO_MIRRORING), pErrorCode); + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + + if(/*run>0 &&*/ dirProps[logicalStart]!=L) { + if(destSize>0) { + *dest++=LRM_CHAR; + } + --destSize; + } + } else { + if(/*run<runCount-1 &&*/ !(MASK_R_AL&DIRPROP_FLAG(dirProps[logicalStart]))) { + if(destSize>0) { + *dest++=RLM_CHAR; + } + --destSize; + } + + runLength=doWriteForward(src, runLength, + dest, destSize, + options, pErrorCode); + if(dest!=NULL) { + dest+=runLength; + } + destSize-=runLength; + + if(/*run>0 &&*/ !(MASK_R_AL&DIRPROP_FLAG(dirProps[logicalStart+runLength-1]))) { + if(destSize>0) { + *dest++=RLM_CHAR; + } + --destSize; + } + } + } + } + } + + return u_terminateUChars(saveDest, destCapacity, destCapacity-destSize, pErrorCode); +} +#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924)) +#pragma optimize( "", on ) +#endif |