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      1 /*
      2 ******************************************************************************
      3 *
      4 *   Copyright (C) 2008-2011, International Business Machines
      5 *   Corporation and others.  All Rights Reserved.
      6 *
      7 ******************************************************************************
      8 *   file name:  uspoof_conf.cpp
      9 *   encoding:   US-ASCII
     10 *   tab size:   8 (not used)
     11 *   indentation:4
     12 *
     13 *   created on: 2009Jan05  (refactoring earlier files)
     14 *   created by: Andy Heninger
     15 *
     16 *   Internal classes for compililing confusable data into its binary (runtime) form.
     17 */
     18 
     19 #include "unicode/utypes.h"
     20 #include "unicode/uspoof.h"
     21 #if !UCONFIG_NO_REGULAR_EXPRESSIONS
     22 #if !UCONFIG_NO_NORMALIZATION
     23 
     24 #include "unicode/unorm.h"
     25 #include "unicode/uregex.h"
     26 #include "unicode/ustring.h"
     27 #include "cmemory.h"
     28 #include "uspoof_impl.h"
     29 #include "uhash.h"
     30 #include "uvector.h"
     31 #include "uassert.h"
     32 #include "uarrsort.h"
     33 #include "uspoof_conf.h"
     34 
     35 U_NAMESPACE_USE
     36 
     37 
     38 //---------------------------------------------------------------------
     39 //
     40 //  buildConfusableData   Compile the source confusable data, as defined by
     41 //                        the Unicode data file confusables.txt, into the binary
     42 //                        structures used by the confusable detector.
     43 //
     44 //                        The binary structures are described in uspoof_impl.h
     45 //
     46 //     1.  parse the data, building 4 hash tables, one each for the SL, SA, ML and MA
     47 //         tables.  Each maps from a UChar32 to a String.
     48 //
     49 //     2.  Sort all of the strings encountered by length, since they will need to
     50 //         be stored in that order in the final string table.
     51 //
     52 //     3.  Build a list of keys (UChar32s) from the four mapping tables.  Sort the
     53 //         list because that will be the ordering of our runtime table.
     54 //
     55 //     4.  Generate the run time string table.  This is generated before the key & value
     56 //         tables because we need the string indexes when building those tables.
     57 //
     58 //     5.  Build the run-time key and value tables.  These are parallel tables, and are built
     59 //         at the same time
     60 //
     61 
     62 SPUString::SPUString(UnicodeString *s) {
     63     fStr = s;
     64     fStrTableIndex = 0;
     65 }
     66 
     67 
     68 SPUString::~SPUString() {
     69     delete fStr;
     70 }
     71 
     72 
     73 SPUStringPool::SPUStringPool(UErrorCode &status) : fVec(NULL), fHash(NULL) {
     74     fVec = new UVector(status);
     75     fHash = uhash_open(uhash_hashUnicodeString,           // key hash function
     76                        uhash_compareUnicodeString,        // Key Comparator
     77                        NULL,                              // Value Comparator
     78                        &status);
     79 }
     80 
     81 
     82 SPUStringPool::~SPUStringPool() {
     83     int i;
     84     for (i=fVec->size()-1; i>=0; i--) {
     85         SPUString *s = static_cast<SPUString *>(fVec->elementAt(i));
     86         delete s;
     87     }
     88     delete fVec;
     89     uhash_close(fHash);
     90 }
     91 
     92 
     93 int32_t SPUStringPool::size() {
     94     return fVec->size();
     95 }
     96 
     97 SPUString *SPUStringPool::getByIndex(int32_t index) {
     98     SPUString *retString = (SPUString *)fVec->elementAt(index);
     99     return retString;
    100 }
    101 
    102 
    103 // Comparison function for ordering strings in the string pool.
    104 // Compare by length first, then, within a group of the same length,
    105 // by code point order.
    106 // Conforms to the type signature for a USortComparator in uvector.h
    107 
    108 static int8_t U_CALLCONV SPUStringCompare(UHashTok left, UHashTok right) {
    109 	const SPUString *sL = const_cast<const SPUString *>(
    110         static_cast<SPUString *>(left.pointer));
    111  	const SPUString *sR = const_cast<const SPUString *>(
    112  	    static_cast<SPUString *>(right.pointer));
    113     int32_t lenL = sL->fStr->length();
    114     int32_t lenR = sR->fStr->length();
    115     if (lenL < lenR) {
    116         return -1;
    117     } else if (lenL > lenR) {
    118         return 1;
    119     } else {
    120         return sL->fStr->compare(*(sR->fStr));
    121     }
    122 }
    123 
    124 void SPUStringPool::sort(UErrorCode &status) {
    125     fVec->sort(SPUStringCompare, status);
    126 }
    127 
    128 
    129 SPUString *SPUStringPool::addString(UnicodeString *src, UErrorCode &status) {
    130     SPUString *hashedString = static_cast<SPUString *>(uhash_get(fHash, src));
    131     if (hashedString != NULL) {
    132         delete src;
    133     } else {
    134         hashedString = new SPUString(src);
    135         uhash_put(fHash, src, hashedString, &status);
    136         fVec->addElement(hashedString, status);
    137     }
    138     return hashedString;
    139 }
    140 
    141 
    142 
    143 ConfusabledataBuilder::ConfusabledataBuilder(SpoofImpl *spImpl, UErrorCode &status) :
    144     fSpoofImpl(spImpl),
    145     fInput(NULL),
    146     fSLTable(NULL),
    147     fSATable(NULL),
    148     fMLTable(NULL),
    149     fMATable(NULL),
    150     fKeySet(NULL),
    151     fKeyVec(NULL),
    152     fValueVec(NULL),
    153     fStringTable(NULL),
    154     fStringLengthsTable(NULL),
    155     stringPool(NULL),
    156     fParseLine(NULL),
    157     fParseHexNum(NULL),
    158     fLineNum(0)
    159 {
    160     if (U_FAILURE(status)) {
    161         return;
    162     }
    163     fSLTable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
    164     fSATable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
    165     fMLTable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
    166     fMATable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
    167     fKeySet     = new UnicodeSet();
    168     fKeyVec     = new UVector(status);
    169     fValueVec   = new UVector(status);
    170     stringPool = new SPUStringPool(status);
    171 }
    172 
    173 
    174 ConfusabledataBuilder::~ConfusabledataBuilder() {
    175     uprv_free(fInput);
    176     uregex_close(fParseLine);
    177     uregex_close(fParseHexNum);
    178     uhash_close(fSLTable);
    179     uhash_close(fSATable);
    180     uhash_close(fMLTable);
    181     uhash_close(fMATable);
    182     delete fKeySet;
    183     delete fKeyVec;
    184     delete fStringTable;
    185     delete fStringLengthsTable;
    186     delete fValueVec;
    187     delete stringPool;
    188 }
    189 
    190 
    191 void ConfusabledataBuilder::buildConfusableData(SpoofImpl * spImpl, const char * confusables,
    192     int32_t confusablesLen, int32_t *errorType, UParseError *pe, UErrorCode &status) {
    193 
    194     if (U_FAILURE(status)) {
    195         return;
    196     }
    197     ConfusabledataBuilder builder(spImpl, status);
    198     builder.build(confusables, confusablesLen, status);
    199     if (U_FAILURE(status) && errorType != NULL) {
    200         *errorType = USPOOF_SINGLE_SCRIPT_CONFUSABLE;
    201         pe->line = builder.fLineNum;
    202     }
    203 }
    204 
    205 
    206 void ConfusabledataBuilder::build(const char * confusables, int32_t confusablesLen,
    207                UErrorCode &status) {
    208 
    209     // Convert the user input data from UTF-8 to UChar (UTF-16)
    210     int32_t inputLen = 0;
    211     if (U_FAILURE(status)) {
    212         return;
    213     }
    214     u_strFromUTF8(NULL, 0, &inputLen, confusables, confusablesLen, &status);
    215     if (status != U_BUFFER_OVERFLOW_ERROR) {
    216         return;
    217     }
    218     status = U_ZERO_ERROR;
    219     fInput = static_cast<UChar *>(uprv_malloc((inputLen+1) * sizeof(UChar)));
    220     if (fInput == NULL) {
    221         status = U_MEMORY_ALLOCATION_ERROR;
    222         return;
    223     }
    224     u_strFromUTF8(fInput, inputLen+1, NULL, confusables, confusablesLen, &status);
    225 
    226 
    227     // Regular Expression to parse a line from Confusables.txt.  The expression will match
    228     // any line.  What was matched is determined by examining which capture groups have a match.
    229     //   Capture Group 1:  the source char
    230     //   Capture Group 2:  the replacement chars
    231     //   Capture Group 3-6  the table type, SL, SA, ML, or MA
    232     //   Capture Group 7:  A blank or comment only line.
    233     //   Capture Group 8:  A syntactically invalid line.  Anything that didn't match before.
    234     // Example Line from the confusables.txt source file:
    235     //   "1D702 ;	006E 0329 ;	SL	# MATHEMATICAL ITALIC SMALL ETA ... "
    236     UnicodeString pattern(
    237         "(?m)^[ \\t]*([0-9A-Fa-f]+)[ \\t]+;"      // Match the source char
    238         "[ \\t]*([0-9A-Fa-f]+"                    // Match the replacement char(s)
    239            "(?:[ \\t]+[0-9A-Fa-f]+)*)[ \\t]*;"    //     (continued)
    240         "\\s*(?:(SL)|(SA)|(ML)|(MA))"             // Match the table type
    241         "[ \\t]*(?:#.*?)?$"                       // Match any trailing #comment
    242         "|^([ \\t]*(?:#.*?)?)$"       // OR match empty lines or lines with only a #comment
    243         "|^(.*?)$", -1, US_INV);      // OR match any line, which catches illegal lines.
    244     // TODO: Why are we using the regex C API here? C++ would just take UnicodeString...
    245     fParseLine = uregex_open(pattern.getBuffer(), pattern.length(), 0, NULL, &status);
    246 
    247     // Regular expression for parsing a hex number out of a space-separated list of them.
    248     //   Capture group 1 gets the number, with spaces removed.
    249     pattern = UNICODE_STRING_SIMPLE("\\s*([0-9A-F]+)");
    250     fParseHexNum = uregex_open(pattern.getBuffer(), pattern.length(), 0, NULL, &status);
    251 
    252     // Zap any Byte Order Mark at the start of input.  Changing it to a space is benign
    253     //   given the syntax of the input.
    254     if (*fInput == 0xfeff) {
    255         *fInput = 0x20;
    256     }
    257 
    258     // Parse the input, one line per iteration of this loop.
    259     uregex_setText(fParseLine, fInput, inputLen, &status);
    260     while (uregex_findNext(fParseLine, &status)) {
    261         fLineNum++;
    262         if (uregex_start(fParseLine, 7, &status) >= 0) {
    263             // this was a blank or comment line.
    264             continue;
    265         }
    266         if (uregex_start(fParseLine, 8, &status) >= 0) {
    267             // input file syntax error.
    268             status = U_PARSE_ERROR;
    269             return;
    270         }
    271 
    272         // We have a good input line.  Extract the key character and mapping string, and
    273         //    put them into the appropriate mapping table.
    274         UChar32 keyChar = SpoofImpl::ScanHex(fInput, uregex_start(fParseLine, 1, &status),
    275                           uregex_end(fParseLine, 1, &status), status);
    276 
    277         int32_t mapStringStart = uregex_start(fParseLine, 2, &status);
    278         int32_t mapStringLength = uregex_end(fParseLine, 2, &status) - mapStringStart;
    279         uregex_setText(fParseHexNum, &fInput[mapStringStart], mapStringLength, &status);
    280 
    281         UnicodeString  *mapString = new UnicodeString();
    282         if (mapString == NULL) {
    283             status = U_MEMORY_ALLOCATION_ERROR;
    284             return;
    285         }
    286         while (uregex_findNext(fParseHexNum, &status)) {
    287             UChar32 c = SpoofImpl::ScanHex(&fInput[mapStringStart], uregex_start(fParseHexNum, 1, &status),
    288                                  uregex_end(fParseHexNum, 1, &status), status);
    289             mapString->append(c);
    290         }
    291         U_ASSERT(mapString->length() >= 1);
    292 
    293         // Put the map (value) string into the string pool
    294         // This a little like a Java intern() - any duplicates will be eliminated.
    295         SPUString *smapString = stringPool->addString(mapString, status);
    296 
    297         // Add the UChar32 -> string mapping to the appropriate table.
    298         UHashtable *table = uregex_start(fParseLine, 3, &status) >= 0 ? fSLTable :
    299                             uregex_start(fParseLine, 4, &status) >= 0 ? fSATable :
    300                             uregex_start(fParseLine, 5, &status) >= 0 ? fMLTable :
    301                             uregex_start(fParseLine, 6, &status) >= 0 ? fMATable :
    302                             NULL;
    303         U_ASSERT(table != NULL);
    304         uhash_iput(table, keyChar, smapString, &status);
    305         fKeySet->add(keyChar);
    306         if (U_FAILURE(status)) {
    307             return;
    308         }
    309     }
    310 
    311     // Input data is now all parsed and collected.
    312     // Now create the run-time binary form of the data.
    313     //
    314     // This is done in two steps.  First the data is assembled into vectors and strings,
    315     //   for ease of construction, then the contents of these collections are dumped
    316     //   into the actual raw-bytes data storage.
    317 
    318     // Build up the string array, and record the index of each string therein
    319     //  in the (build time only) string pool.
    320     // Strings of length one are not entered into the strings array.
    321     // At the same time, build up the string lengths table, which records the
    322     // position in the string table of the first string of each length >= 4.
    323     // (Strings in the table are sorted by length)
    324     stringPool->sort(status);
    325     fStringTable = new UnicodeString();
    326     fStringLengthsTable = new UVector(status);
    327     int32_t previousStringLength = 0;
    328     int32_t previousStringIndex  = 0;
    329     int32_t poolSize = stringPool->size();
    330     int32_t i;
    331     for (i=0; i<poolSize; i++) {
    332         SPUString *s = stringPool->getByIndex(i);
    333         int32_t strLen = s->fStr->length();
    334         int32_t strIndex = fStringTable->length();
    335         U_ASSERT(strLen >= previousStringLength);
    336         if (strLen == 1) {
    337             // strings of length one do not get an entry in the string table.
    338             // Keep the single string character itself here, which is the same
    339             //  convention that is used in the final run-time string table index.
    340             s->fStrTableIndex = s->fStr->charAt(0);
    341         } else {
    342             if ((strLen > previousStringLength) && (previousStringLength >= 4)) {
    343                 fStringLengthsTable->addElement(previousStringIndex, status);
    344                 fStringLengthsTable->addElement(previousStringLength, status);
    345             }
    346             s->fStrTableIndex = strIndex;
    347             fStringTable->append(*(s->fStr));
    348         }
    349         previousStringLength = strLen;
    350         previousStringIndex  = strIndex;
    351     }
    352     // Make the final entry to the string lengths table.
    353     //   (it holds an entry for the _last_ string of each length, so adding the
    354     //    final one doesn't happen in the main loop because no longer string was encountered.)
    355     if (previousStringLength >= 4) {
    356         fStringLengthsTable->addElement(previousStringIndex, status);
    357         fStringLengthsTable->addElement(previousStringLength, status);
    358     }
    359 
    360     // Construct the compile-time Key and Value tables
    361     //
    362     // For each key code point, check which mapping tables it applies to,
    363     //   and create the final data for the key & value structures.
    364     //
    365     //   The four logical mapping tables are conflated into one combined table.
    366     //   If multiple logical tables have the same mapping for some key, they
    367     //     share a single entry in the combined table.
    368     //   If more than one mapping exists for the same key code point, multiple
    369     //     entries will be created in the table
    370 
    371     for (int32_t range=0; range<fKeySet->getRangeCount(); range++) {
    372         // It is an oddity of the UnicodeSet API that simply enumerating the contained
    373         //   code points requires a nested loop.
    374         for (UChar32 keyChar=fKeySet->getRangeStart(range);
    375                 keyChar <= fKeySet->getRangeEnd(range); keyChar++) {
    376             addKeyEntry(keyChar, fSLTable, USPOOF_SL_TABLE_FLAG, status);
    377             addKeyEntry(keyChar, fSATable, USPOOF_SA_TABLE_FLAG, status);
    378             addKeyEntry(keyChar, fMLTable, USPOOF_ML_TABLE_FLAG, status);
    379             addKeyEntry(keyChar, fMATable, USPOOF_MA_TABLE_FLAG, status);
    380         }
    381     }
    382 
    383     // Put the assembled data into the flat runtime array
    384     outputData(status);
    385 
    386     // All of the intermediate allocated data belongs to the ConfusabledataBuilder
    387     //  object  (this), and is deleted in the destructor.
    388     return;
    389 }
    390 
    391 //
    392 // outputData     The confusable data has been compiled and stored in intermediate
    393 //                collections and strings.  Copy it from there to the final flat
    394 //                binary array.
    395 //
    396 //                Note that as each section is added to the output data, the
    397 //                expand (reserveSpace() function will likely relocate it in memory.
    398 //                Be careful with pointers.
    399 //
    400 void ConfusabledataBuilder::outputData(UErrorCode &status) {
    401 
    402     U_ASSERT(fSpoofImpl->fSpoofData->fDataOwned == TRUE);
    403 
    404     //  The Key Table
    405     //     While copying the keys to the runtime array,
    406     //       also sanity check that they are sorted.
    407 
    408     int32_t numKeys = fKeyVec->size();
    409     int32_t *keys =
    410         static_cast<int32_t *>(fSpoofImpl->fSpoofData->reserveSpace(numKeys*sizeof(int32_t), status));
    411     if (U_FAILURE(status)) {
    412         return;
    413     }
    414     int i;
    415     int32_t previousKey = 0;
    416     for (i=0; i<numKeys; i++) {
    417         int32_t key =  fKeyVec->elementAti(i);
    418         U_ASSERT((key & 0x00ffffff) >= (previousKey & 0x00ffffff));
    419         U_ASSERT((key & 0xff000000) != 0);
    420         keys[i] = key;
    421         previousKey = key;
    422     }
    423     SpoofDataHeader *rawData = fSpoofImpl->fSpoofData->fRawData;
    424     rawData->fCFUKeys = (int32_t)((char *)keys - (char *)rawData);
    425     rawData->fCFUKeysSize = numKeys;
    426     fSpoofImpl->fSpoofData->fCFUKeys = keys;
    427 
    428 
    429     // The Value Table, parallels the key table
    430     int32_t numValues = fValueVec->size();
    431     U_ASSERT(numKeys == numValues);
    432     uint16_t *values =
    433         static_cast<uint16_t *>(fSpoofImpl->fSpoofData->reserveSpace(numKeys*sizeof(uint16_t), status));
    434     if (U_FAILURE(status)) {
    435         return;
    436     }
    437     for (i=0; i<numValues; i++) {
    438         uint32_t value = static_cast<uint32_t>(fValueVec->elementAti(i));
    439         U_ASSERT(value < 0xffff);
    440         values[i] = static_cast<uint16_t>(value);
    441     }
    442     rawData = fSpoofImpl->fSpoofData->fRawData;
    443     rawData->fCFUStringIndex = (int32_t)((char *)values - (char *)rawData);
    444     rawData->fCFUStringIndexSize = numValues;
    445     fSpoofImpl->fSpoofData->fCFUValues = values;
    446 
    447     // The Strings Table.
    448 
    449     uint32_t stringsLength = fStringTable->length();
    450     // Reserve an extra space so the string will be nul-terminated.  This is
    451     // only a convenience, for when debugging; it is not needed otherwise.
    452     UChar *strings =
    453         static_cast<UChar *>(fSpoofImpl->fSpoofData->reserveSpace(stringsLength*sizeof(UChar)+2, status));
    454     if (U_FAILURE(status)) {
    455         return;
    456     }
    457     fStringTable->extract(strings, stringsLength+1, status);
    458     rawData = fSpoofImpl->fSpoofData->fRawData;
    459     U_ASSERT(rawData->fCFUStringTable == 0);
    460     rawData->fCFUStringTable = (int32_t)((char *)strings - (char *)rawData);
    461     rawData->fCFUStringTableLen = stringsLength;
    462     fSpoofImpl->fSpoofData->fCFUStrings = strings;
    463 
    464     // The String Lengths Table
    465     //    While copying into the runtime array do some sanity checks on the values
    466     //    Each complete entry contains two fields, an index and an offset.
    467     //    Lengths should increase with each entry.
    468     //    Offsets should be less than the size of the string table.
    469     int32_t lengthTableLength = fStringLengthsTable->size();
    470     uint16_t *stringLengths =
    471         static_cast<uint16_t *>(fSpoofImpl->fSpoofData->reserveSpace(lengthTableLength*sizeof(uint16_t), status));
    472     if (U_FAILURE(status)) {
    473         return;
    474     }
    475     int32_t destIndex = 0;
    476     uint32_t previousLength = 0;
    477     for (i=0; i<lengthTableLength; i+=2) {
    478         uint32_t offset = static_cast<uint32_t>(fStringLengthsTable->elementAti(i));
    479         uint32_t length = static_cast<uint32_t>(fStringLengthsTable->elementAti(i+1));
    480         U_ASSERT(offset < stringsLength);
    481         U_ASSERT(length < 40);
    482         U_ASSERT(length > previousLength);
    483         stringLengths[destIndex++] = static_cast<uint16_t>(offset);
    484         stringLengths[destIndex++] = static_cast<uint16_t>(length);
    485         previousLength = length;
    486     }
    487     rawData = fSpoofImpl->fSpoofData->fRawData;
    488     rawData->fCFUStringLengths = (int32_t)((char *)stringLengths - (char *)rawData);
    489     // Note: StringLengthsSize in the raw data is the number of complete entries,
    490     //       each consisting of a pair of 16 bit values, hence the divide by 2.
    491     rawData->fCFUStringLengthsSize = lengthTableLength / 2;
    492     fSpoofImpl->fSpoofData->fCFUStringLengths =
    493         reinterpret_cast<SpoofStringLengthsElement *>(stringLengths);
    494 }
    495 
    496 
    497 
    498 //  addKeyEntry   Construction of the confusable Key and Mapping Values tables.
    499 //                This is an intermediate point in the building process.
    500 //                We already have the mappings in the hash tables fSLTable, etc.
    501 //                This function builds corresponding run-time style table entries into
    502 //                  fKeyVec and fValueVec
    503 
    504 void ConfusabledataBuilder::addKeyEntry(
    505     UChar32     keyChar,     // The key character
    506     UHashtable *table,       // The table, one of SATable, MATable, etc.
    507     int32_t     tableFlag,   // One of USPOOF_SA_TABLE_FLAG, etc.
    508     UErrorCode &status) {
    509 
    510     SPUString *targetMapping = static_cast<SPUString *>(uhash_iget(table, keyChar));
    511     if (targetMapping == NULL) {
    512         // No mapping for this key character.
    513         //   (This function is called for all four tables for each key char that
    514         //    is seen anywhere, so this no entry cases are very much expected.)
    515         return;
    516     }
    517 
    518     // Check whether there is already an entry with the correct mapping.
    519     // If so, simply set the flag in the keyTable saying that the existing entry
    520     // applies to the table that we're doing now.
    521 
    522     UBool keyHasMultipleValues = FALSE;
    523     int32_t i;
    524     for (i=fKeyVec->size()-1; i>=0 ; i--) {
    525         int32_t key = fKeyVec->elementAti(i);
    526         if ((key & 0x0ffffff) != keyChar) {
    527             // We have now checked all existing key entries for this key char (if any)
    528             //  without finding one with the same mapping.
    529             break;
    530         }
    531         UnicodeString mapping = getMapping(i);
    532         if (mapping == *(targetMapping->fStr)) {
    533             // The run time entry we are currently testing has the correct mapping.
    534             // Set the flag in it indicating that it applies to the new table also.
    535             key |= tableFlag;
    536             fKeyVec->setElementAt(key, i);
    537             return;
    538         }
    539         keyHasMultipleValues = TRUE;
    540     }
    541 
    542     // Need to add a new entry to the binary data being built for this mapping.
    543     // Includes adding entries to both the key table and the parallel values table.
    544 
    545     int32_t newKey = keyChar | tableFlag;
    546     if (keyHasMultipleValues) {
    547         newKey |= USPOOF_KEY_MULTIPLE_VALUES;
    548     }
    549     int32_t adjustedMappingLength = targetMapping->fStr->length() - 1;
    550     if (adjustedMappingLength>3) {
    551         adjustedMappingLength = 3;
    552     }
    553     newKey |= adjustedMappingLength << USPOOF_KEY_LENGTH_SHIFT;
    554 
    555     int32_t newData = targetMapping->fStrTableIndex;
    556 
    557     fKeyVec->addElement(newKey, status);
    558     fValueVec->addElement(newData, status);
    559 
    560     // If the preceding key entry is for the same key character (but with a different mapping)
    561     //   set the multiple-values flag on it.
    562     if (keyHasMultipleValues) {
    563         int32_t previousKeyIndex = fKeyVec->size() - 2;
    564         int32_t previousKey = fKeyVec->elementAti(previousKeyIndex);
    565         previousKey |= USPOOF_KEY_MULTIPLE_VALUES;
    566         fKeyVec->setElementAt(previousKey, previousKeyIndex);
    567     }
    568 }
    569 
    570 
    571 
    572 UnicodeString ConfusabledataBuilder::getMapping(int32_t index) {
    573     int32_t key = fKeyVec->elementAti(index);
    574     int32_t value = fValueVec->elementAti(index);
    575     int32_t length = USPOOF_KEY_LENGTH_FIELD(key);
    576     int32_t lastIndexWithLen;
    577     switch (length) {
    578       case 0:
    579         return UnicodeString(static_cast<UChar>(value));
    580       case 1:
    581       case 2:
    582         return UnicodeString(*fStringTable, value, length+1);
    583       case 3:
    584         length = 0;
    585         int32_t i;
    586         for (i=0; i<fStringLengthsTable->size(); i+=2) {
    587             lastIndexWithLen = fStringLengthsTable->elementAti(i);
    588             if (value <= lastIndexWithLen) {
    589                 length = fStringLengthsTable->elementAti(i+1);
    590                 break;
    591             }
    592         }
    593         U_ASSERT(length>=3);
    594         return UnicodeString(*fStringTable, value, length);
    595       default:
    596         U_ASSERT(FALSE);
    597     }
    598     return UnicodeString();
    599 }
    600 
    601 #endif
    602 #endif // !UCONFIG_NO_REGULAR_EXPRESSIONS
    603 
    604