Check in the pristine copy of ICU 4.6...

icu46/source/i18n/uspoof_conf.cpp

+/*
+******************************************************************************
+*
+*   Copyright (C) 2008-2010, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+******************************************************************************
+*   file name:  uspoof_conf.cpp
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2009Jan05  (refactoring earlier files)
+*   created by: Andy Heninger
+*
+*   Internal classes for compililing confusable data into its binary (runtime) form.
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/uspoof.h"
+#if !UCONFIG_NO_REGULAR_EXPRESSIONS
+#if !UCONFIG_NO_NORMALIZATION
+
+#include "unicode/unorm.h"
+#include "unicode/uregex.h"
+#include "unicode/ustring.h"
+#include "cmemory.h"
+#include "uspoof_impl.h"
+#include "uhash.h"
+#include "uvector.h"
+#include "uassert.h"
+#include "uarrsort.h"
+#include "uspoof_conf.h"
+
+U_NAMESPACE_USE
+
+
+//---------------------------------------------------------------------
+//
+//  buildConfusableData   Compile the source confusable data, as defined by
+//                        the Unicode data file confusables.txt, into the binary
+//                        structures used by the confusable detector.
+//
+//                        The binary structures are described in uspoof_impl.h
+//
+//     1.  parse the data, building 4 hash tables, one each for the SL, SA, ML and MA
+//         tables.  Each maps from a UChar32 to a String.
+//
+//     2.  Sort all of the strings encountered by length, since they will need to
+//         be stored in that order in the final string table.
+//
+//     3.  Build a list of keys (UChar32s) from the four mapping tables.  Sort the
+//         list because that will be the ordering of our runtime table.
+//
+//     4.  Generate the run time string table.  This is generated before the key & value
+//         tables because we need the string indexes when building those tables.
+//
+//     5.  Build the run-time key and value tables.  These are parallel tables, and are built
+//         at the same time
+//
+
+SPUString::SPUString(UnicodeString *s) {
+    fStr = s;
+    fStrTableIndex = 0;
+}
+
+
+SPUString::~SPUString() {
+    delete fStr;
+}
+
+
+SPUStringPool::SPUStringPool(UErrorCode &status) : fVec(NULL), fHash(NULL) {
+    fVec = new UVector(status);
+    fHash = uhash_open(uhash_hashUnicodeString,           // key hash function
+                       uhash_compareUnicodeString,        // Key Comparator
+                       NULL,                              // Value Comparator
+                       &status);
+}
+
+
+SPUStringPool::~SPUStringPool() {
+    int i;
+    for (i=fVec->size()-1; i>=0; i--) {
+        SPUString *s = static_cast<SPUString *>(fVec->elementAt(i));
+        delete s;
+    }
+    delete fVec;
+    uhash_close(fHash);
+}
+
+
+int32_t SPUStringPool::size() {
+    return fVec->size();
+}
+
+SPUString *SPUStringPool::getByIndex(int32_t index) {
+    SPUString *retString = (SPUString *)fVec->elementAt(index);
+    return retString;
+}
+
+
+// Comparison function for ordering strings in the string pool.
+// Compare by length first, then, within a group of the same length,
+// by code point order.
+// Conforms to the type signature for a USortComparator in uvector.h
+
+static int8_t U_CALLCONV SPUStringCompare(UHashTok left, UHashTok right) {
+        const SPUString *sL = const_cast<const SPUString *>(
+        static_cast<SPUString *>(left.pointer));
+        const SPUString *sR = const_cast<const SPUString *>(
+            static_cast<SPUString *>(right.pointer));
+    int32_t lenL = sL->fStr->length();
+    int32_t lenR = sR->fStr->length();
+    if (lenL < lenR) {
+        return -1;
+    } else if (lenL > lenR) {
+        return 1;
+    } else {
+        return sL->fStr->compare(*(sR->fStr));
+    }
+}
+
+void SPUStringPool::sort(UErrorCode &status) {
+    fVec->sort(SPUStringCompare, status);
+}
+
+
+SPUString *SPUStringPool::addString(UnicodeString *src, UErrorCode &status) {
+    SPUString *hashedString = static_cast<SPUString *>(uhash_get(fHash, src));
+    if (hashedString != NULL) {
+        delete src;
+    } else {
+        hashedString = new SPUString(src);
+        uhash_put(fHash, src, hashedString, &status);
+        fVec->addElement(hashedString, status);
+    }
+    return hashedString;
+}
+
+
+
+ConfusabledataBuilder::ConfusabledataBuilder(SpoofImpl *spImpl, UErrorCode &status) :
+    fSpoofImpl(spImpl),
+    fInput(NULL),
+    fSLTable(NULL),
+    fSATable(NULL),
+    fMLTable(NULL),
+    fMATable(NULL),
+    fKeySet(NULL),
+    fKeyVec(NULL),
+    fValueVec(NULL),
+    fStringTable(NULL),
+    fStringLengthsTable(NULL),
+    stringPool(NULL),
+    fParseLine(NULL),
+    fParseHexNum(NULL),
+    fLineNum(0)
+{
+    if (U_FAILURE(status)) {
+        return;
+    }
+    fSLTable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
+    fSATable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
+    fMLTable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
+    fMATable    = uhash_open(uhash_hashLong, uhash_compareLong, NULL, &status);
+    fKeySet     = new UnicodeSet();
+    fKeyVec     = new UVector(status);
+    fValueVec   = new UVector(status);
+    stringPool = new SPUStringPool(status);
+}
+
+
+ConfusabledataBuilder::~ConfusabledataBuilder() {
+    uprv_free(fInput);
+    uregex_close(fParseLine);
+    uregex_close(fParseHexNum);
+    uhash_close(fSLTable);
+    uhash_close(fSATable);
+    uhash_close(fMLTable);
+    uhash_close(fMATable);
+    delete fKeySet;
+    delete fKeyVec;
+    delete fStringTable;
+    delete fStringLengthsTable;
+    delete fValueVec;
+    delete stringPool;
+}
+
+
+void ConfusabledataBuilder::buildConfusableData(SpoofImpl * spImpl, const char * confusables,
+    int32_t confusablesLen, int32_t *errorType, UParseError *pe, UErrorCode &status) {
+
+    if (U_FAILURE(status)) {
+        return;
+    }
+    ConfusabledataBuilder builder(spImpl, status);
+    builder.build(confusables, confusablesLen, status);
+    if (U_FAILURE(status) && errorType != NULL) {
+        *errorType = USPOOF_SINGLE_SCRIPT_CONFUSABLE;
+        pe->line = builder.fLineNum;
+    }
+}
+
+
+void ConfusabledataBuilder::build(const char * confusables, int32_t confusablesLen,
+               UErrorCode &status) {
+
+    // Convert the user input data from UTF-8 to UChar (UTF-16)
+    int32_t inputLen = 0;
+    if (U_FAILURE(status)) {
+        return;
+    }
+    u_strFromUTF8(NULL, 0, &inputLen, confusables, confusablesLen, &status);
+    if (status != U_BUFFER_OVERFLOW_ERROR) {
+        return;
+    }
+    status = U_ZERO_ERROR;
+    fInput = static_cast<UChar *>(uprv_malloc((inputLen+1) * sizeof(UChar)));
+    if (fInput == NULL) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+    }
+    u_strFromUTF8(fInput, inputLen+1, NULL, confusables, confusablesLen, &status);
+
+
+    // Regular Expression to parse a line from Confusables.txt.  The expression will match
+    // any line.  What was matched is determined by examining which capture groups have a match.
+    //   Capture Group 1:  the source char
+    //   Capture Group 2:  the replacement chars
+    //   Capture Group 3-6  the table type, SL, SA, ML, or MA
+    //   Capture Group 7:  A blank or comment only line.
+    //   Capture Group 8:  A syntactically invalid line.  Anything that didn't match before.
+    // Example Line from the confusables.txt source file:
+    //   "1D702 ;       006E 0329 ;     SL      # MATHEMATICAL ITALIC SMALL ETA ... "
+    fParseLine = uregex_openC(
+        "(?m)^[ \\t]*([0-9A-Fa-f]+)[ \\t]+;"      // Match the source char
+        "[ \\t]*([0-9A-Fa-f]+"                    // Match the replacement char(s)
+           "(?:[ \\t]+[0-9A-Fa-f]+)*)[ \\t]*;"    //     (continued)
+        "\\s*(?:(SL)|(SA)|(ML)|(MA))"             // Match the table type
+        "[ \\t]*(?:#.*?)?$"                       // Match any trailing #comment
+        "|^([ \\t]*(?:#.*?)?)$"       // OR match empty lines or lines with only a #comment
+        "|^(.*?)$",                   // OR match any line, which catches illegal lines.
+        0, NULL, &status);
+
+    // Regular expression for parsing a hex number out of a space-separated list of them.
+    //   Capture group 1 gets the number, with spaces removed.
+    fParseHexNum = uregex_openC("\\s*([0-9A-F]+)", 0, NULL, &status);
+
+    // Zap any Byte Order Mark at the start of input.  Changing it to a space is benign
+    //   given the syntax of the input.
+    if (*fInput == 0xfeff) {
+        *fInput = 0x20;
+    }
+
+    // Parse the input, one line per iteration of this loop.
+    uregex_setText(fParseLine, fInput, inputLen, &status);
+    while (uregex_findNext(fParseLine, &status)) {
+        fLineNum++;
+        if (uregex_start(fParseLine, 7, &status) >= 0) {
+            // this was a blank or comment line.
+            continue;
+        }
+        if (uregex_start(fParseLine, 8, &status) >= 0) {
+            // input file syntax error.
+            status = U_PARSE_ERROR;
+            return;
+        }
+
+        // We have a good input line.  Extract the key character and mapping string, and
+        //    put them into the appropriate mapping table.
+        UChar32 keyChar = SpoofImpl::ScanHex(fInput, uregex_start(fParseLine, 1, &status),
+                          uregex_end(fParseLine, 1, &status), status);
+
+        int32_t mapStringStart = uregex_start(fParseLine, 2, &status);
+        int32_t mapStringLength = uregex_end(fParseLine, 2, &status) - mapStringStart;
+        uregex_setText(fParseHexNum, &fInput[mapStringStart], mapStringLength, &status);
+
+        UnicodeString  *mapString = new UnicodeString();
+        if (mapString == NULL) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return;
+        }
+        while (uregex_findNext(fParseHexNum, &status)) {
+            UChar32 c = SpoofImpl::ScanHex(&fInput[mapStringStart], uregex_start(fParseHexNum, 1, &status),
+                                 uregex_end(fParseHexNum, 1, &status), status);
+            mapString->append(c);
+        }
+        U_ASSERT(mapString->length() >= 1);
+
+        // Put the map (value) string into the string pool
+        // This a little like a Java intern() - any duplicates will be eliminated.
+        SPUString *smapString = stringPool->addString(mapString, status);
+
+        // Add the UChar32 -> string mapping to the appropriate table.
+        UHashtable *table = uregex_start(fParseLine, 3, &status) >= 0 ? fSLTable :
+                            uregex_start(fParseLine, 4, &status) >= 0 ? fSATable :
+                            uregex_start(fParseLine, 5, &status) >= 0 ? fMLTable :
+                            uregex_start(fParseLine, 6, &status) >= 0 ? fMATable :
+                            NULL;
+        U_ASSERT(table != NULL);
+        uhash_iput(table, keyChar, smapString, &status);
+        fKeySet->add(keyChar);
+        if (U_FAILURE(status)) {
+            return;
+        }
+    }
+
+    // Input data is now all parsed and collected.
+    // Now create the run-time binary form of the data.
+    //
+    // This is done in two steps.  First the data is assembled into vectors and strings,
+    //   for ease of construction, then the contents of these collections are dumped
+    //   into the actual raw-bytes data storage.
+
+    // Build up the string array, and record the index of each string therein
+    //  in the (build time only) string pool.
+    // Strings of length one are not entered into the strings array.
+    // At the same time, build up the string lengths table, which records the
+    // position in the string table of the first string of each length >= 4.
+    // (Strings in the table are sorted by length)
+    stringPool->sort(status);
+    fStringTable = new UnicodeString();
+    fStringLengthsTable = new UVector(status);
+    int32_t previousStringLength = 0;
+    int32_t previousStringIndex  = 0;
+    int32_t poolSize = stringPool->size();
+    int32_t i;
+    for (i=0; i<poolSize; i++) {
+        SPUString *s = stringPool->getByIndex(i);
+        int32_t strLen = s->fStr->length();
+        int32_t strIndex = fStringTable->length();
+        U_ASSERT(strLen >= previousStringLength);
+        if (strLen == 1) {
+            // strings of length one do not get an entry in the string table.
+            // Keep the single string character itself here, which is the same
+            //  convention that is used in the final run-time string table index.
+            s->fStrTableIndex = s->fStr->charAt(0);
+        } else {
+            if ((strLen > previousStringLength) && (previousStringLength >= 4)) {
+                fStringLengthsTable->addElement(previousStringIndex, status);
+                fStringLengthsTable->addElement(previousStringLength, status);
+            }
+            s->fStrTableIndex = strIndex;
+            fStringTable->append(*(s->fStr));
+        }
+        previousStringLength = strLen;
+        previousStringIndex  = strIndex;
+    }
+    // Make the final entry to the string lengths table.
+    //   (it holds an entry for the _last_ string of each length, so adding the
+    //    final one doesn't happen in the main loop because no longer string was encountered.)
+    if (previousStringLength >= 4) {
+        fStringLengthsTable->addElement(previousStringIndex, status);
+        fStringLengthsTable->addElement(previousStringLength, status);
+    }
+
+    // Construct the compile-time Key and Value tables
+    //
+    // For each key code point, check which mapping tables it applies to,
+    //   and create the final data for the key & value structures.
+    //
+    //   The four logical mapping tables are conflated into one combined table.
+    //   If multiple logical tables have the same mapping for some key, they
+    //     share a single entry in the combined table.
+    //   If more than one mapping exists for the same key code point, multiple
+    //     entries will be created in the table
+
+    for (int32_t range=0; range<fKeySet->getRangeCount(); range++) {
+        // It is an oddity of the UnicodeSet API that simply enumerating the contained
+        //   code points requires a nested loop.
+        for (UChar32 keyChar=fKeySet->getRangeStart(range);
+                keyChar <= fKeySet->getRangeEnd(range); keyChar++) {
+            addKeyEntry(keyChar, fSLTable, USPOOF_SL_TABLE_FLAG, status);
+            addKeyEntry(keyChar, fSATable, USPOOF_SA_TABLE_FLAG, status);
+            addKeyEntry(keyChar, fMLTable, USPOOF_ML_TABLE_FLAG, status);
+            addKeyEntry(keyChar, fMATable, USPOOF_MA_TABLE_FLAG, status);
+        }
+    }
+
+    // Put the assembled data into the flat runtime array
+    outputData(status);
+
+    // All of the intermediate allocated data belongs to the ConfusabledataBuilder
+    //  object  (this), and is deleted in the destructor.
+    return;
+}
+
+//
+// outputData     The confusable data has been compiled and stored in intermediate
+//                collections and strings.  Copy it from there to the final flat
+//                binary array.
+//
+//                Note that as each section is added to the output data, the
+//                expand (reserveSpace() function will likely relocate it in memory.
+//                Be careful with pointers.
+//
+void ConfusabledataBuilder::outputData(UErrorCode &status) {
+
+    U_ASSERT(fSpoofImpl->fSpoofData->fDataOwned == TRUE);
+
+    //  The Key Table
+    //     While copying the keys to the runtime array,
+    //       also sanity check that they are sorted.
+
+    int32_t numKeys = fKeyVec->size();
+    int32_t *keys =
+        static_cast<int32_t *>(fSpoofImpl->fSpoofData->reserveSpace(numKeys*sizeof(int32_t), status));
+    if (U_FAILURE(status)) {
+        return;
+    }
+    int i;
+    int32_t previousKey = 0;
+    for (i=0; i<numKeys; i++) {
+        int32_t key =  fKeyVec->elementAti(i);
+        U_ASSERT((key & 0x00ffffff) >= (previousKey & 0x00ffffff));
+        U_ASSERT((key & 0xff000000) != 0);
+        keys[i] = key;
+        previousKey = key;
+    }
+    SpoofDataHeader *rawData = fSpoofImpl->fSpoofData->fRawData;
+    rawData->fCFUKeys = (int32_t)((char *)keys - (char *)rawData);
+    rawData->fCFUKeysSize = numKeys;
+    fSpoofImpl->fSpoofData->fCFUKeys = keys;
+
+
+    // The Value Table, parallels the key table
+    int32_t numValues = fValueVec->size();
+    U_ASSERT(numKeys == numValues);
+    uint16_t *values =
+        static_cast<uint16_t *>(fSpoofImpl->fSpoofData->reserveSpace(numKeys*sizeof(uint16_t), status));
+    if (U_FAILURE(status)) {
+        return;
+    }
+    for (i=0; i<numValues; i++) {
+        uint32_t value = static_cast<uint32_t>(fValueVec->elementAti(i));
+        U_ASSERT(value < 0xffff);
+        values[i] = static_cast<uint16_t>(value);
+    }
+    rawData = fSpoofImpl->fSpoofData->fRawData;
+    rawData->fCFUStringIndex = (int32_t)((char *)values - (char *)rawData);
+    rawData->fCFUStringIndexSize = numValues;
+    fSpoofImpl->fSpoofData->fCFUValues = values;
+
+    // The Strings Table.
+
+    uint32_t stringsLength = fStringTable->length();
+    // Reserve an extra space so the string will be nul-terminated.  This is
+    // only a convenience, for when debugging; it is not needed otherwise.
+    UChar *strings =
+        static_cast<UChar *>(fSpoofImpl->fSpoofData->reserveSpace(stringsLength*sizeof(UChar)+2, status));
+    if (U_FAILURE(status)) {
+        return;
+    }
+    fStringTable->extract(strings, stringsLength+1, status);
+    rawData = fSpoofImpl->fSpoofData->fRawData;
+    U_ASSERT(rawData->fCFUStringTable == 0);
+    rawData->fCFUStringTable = (int32_t)((char *)strings - (char *)rawData);
+    rawData->fCFUStringTableLen = stringsLength;
+    fSpoofImpl->fSpoofData->fCFUStrings = strings;
+
+    // The String Lengths Table
+    //    While copying into the runtime array do some sanity checks on the values
+    //    Each complete entry contains two fields, an index and an offset.
+    //    Lengths should increase with each entry.
+    //    Offsets should be less than the size of the string table.
+    int32_t lengthTableLength = fStringLengthsTable->size();
+    uint16_t *stringLengths =
+        static_cast<uint16_t *>(fSpoofImpl->fSpoofData->reserveSpace(lengthTableLength*sizeof(uint16_t), status));
+    if (U_FAILURE(status)) {
+        return;
+    }
+    int32_t destIndex = 0;
+    uint32_t previousLength = 0;
+    for (i=0; i<lengthTableLength; i+=2) {
+        uint32_t offset = static_cast<uint32_t>(fStringLengthsTable->elementAti(i));
+        uint32_t length = static_cast<uint32_t>(fStringLengthsTable->elementAti(i+1));
+        U_ASSERT(offset < stringsLength);
+        U_ASSERT(length < 40);
+        U_ASSERT(length > previousLength);
+        stringLengths[destIndex++] = static_cast<uint16_t>(offset);
+        stringLengths[destIndex++] = static_cast<uint16_t>(length);
+        previousLength = length;
+    }
+    rawData = fSpoofImpl->fSpoofData->fRawData;
+    rawData->fCFUStringLengths = (int32_t)((char *)stringLengths - (char *)rawData);
+    // Note: StringLengthsSize in the raw data is the number of complete entries,
+    //       each consisting of a pair of 16 bit values, hence the divide by 2.
+    rawData->fCFUStringLengthsSize = lengthTableLength / 2;
+    fSpoofImpl->fSpoofData->fCFUStringLengths =
+        reinterpret_cast<SpoofStringLengthsElement *>(stringLengths);
+}
+
+
+
+//  addKeyEntry   Construction of the confusable Key and Mapping Values tables.
+//                This is an intermediate point in the building process.
+//                We already have the mappings in the hash tables fSLTable, etc.
+//                This function builds corresponding run-time style table entries into
+//                  fKeyVec and fValueVec
+
+void ConfusabledataBuilder::addKeyEntry(
+    UChar32     keyChar,     // The key character
+    UHashtable *table,       // The table, one of SATable, MATable, etc.
+    int32_t     tableFlag,   // One of USPOOF_SA_TABLE_FLAG, etc.
+    UErrorCode &status) {
+
+    SPUString *targetMapping = static_cast<SPUString *>(uhash_iget(table, keyChar));
+    if (targetMapping == NULL) {
+        // No mapping for this key character.
+        //   (This function is called for all four tables for each key char that
+        //    is seen anywhere, so this no entry cases are very much expected.)
+        return;
+    }
+
+    // Check whether there is already an entry with the correct mapping.
+    // If so, simply set the flag in the keyTable saying that the existing entry
+    // applies to the table that we're doing now.
+
+    UBool keyHasMultipleValues = FALSE;
+    int32_t i;
+    for (i=fKeyVec->size()-1; i>=0 ; i--) {
+        int32_t key = fKeyVec->elementAti(i);
+        if ((key & 0x0ffffff) != keyChar) {
+            // We have now checked all existing key entries for this key char (if any)
+            //  without finding one with the same mapping.
+            break;
+        }
+        UnicodeString mapping = getMapping(i);
+        if (mapping == *(targetMapping->fStr)) {
+            // The run time entry we are currently testing has the correct mapping.
+            // Set the flag in it indicating that it applies to the new table also.
+            key |= tableFlag;
+            fKeyVec->setElementAt(key, i);
+            return;
+        }
+        keyHasMultipleValues = TRUE;
+    }
+
+    // Need to add a new entry to the binary data being built for this mapping.
+    // Includes adding entries to both the key table and the parallel values table.
+
+    int32_t newKey = keyChar | tableFlag;
+    if (keyHasMultipleValues) {
+        newKey |= USPOOF_KEY_MULTIPLE_VALUES;
+    }
+    int32_t adjustedMappingLength = targetMapping->fStr->length() - 1;
+    if (adjustedMappingLength>3) {
+        adjustedMappingLength = 3;
+    }
+    newKey |= adjustedMappingLength << USPOOF_KEY_LENGTH_SHIFT;
+
+    int32_t newData = targetMapping->fStrTableIndex;
+
+    fKeyVec->addElement(newKey, status);
+    fValueVec->addElement(newData, status);
+
+    // If the preceding key entry is for the same key character (but with a different mapping)
+    //   set the multiple-values flag on it.
+    if (keyHasMultipleValues) {
+        int32_t previousKeyIndex = fKeyVec->size() - 2;
+        int32_t previousKey = fKeyVec->elementAti(previousKeyIndex);
+        previousKey |= USPOOF_KEY_MULTIPLE_VALUES;
+        fKeyVec->setElementAt(previousKey, previousKeyIndex);
+    }
+}
+
+
+
+UnicodeString ConfusabledataBuilder::getMapping(int32_t index) {
+    int32_t key = fKeyVec->elementAti(index);
+    int32_t value = fValueVec->elementAti(index);
+    int32_t length = USPOOF_KEY_LENGTH_FIELD(key);
+    int32_t lastIndexWithLen;
+    switch (length) {
+      case 0:
+        return UnicodeString(static_cast<UChar>(value));
+      case 1:
+      case 2:
+        return UnicodeString(*fStringTable, value, length+1);
+      case 3:
+        length = 0;
+        int32_t i;
+        for (i=0; i<fStringLengthsTable->size(); i+=2) {
+            lastIndexWithLen = fStringLengthsTable->elementAti(i);
+            if (value <= lastIndexWithLen) {
+                length = fStringLengthsTable->elementAti(i+1);
+                break;
+            }
+        }
+        U_ASSERT(length>=3);
+        return UnicodeString(*fStringTable, value, length);
+      default:
+        U_ASSERT(FALSE);
+    }
+    return UnicodeString();
+}
+
+#endif
+#endif // !UCONFIG_NO_REGULAR_EXPRESSIONS
+