const CollationKey&
CollationKey::operator=(const CollationKey& other)
{
    if (this != &other)
    {
        if (other.isBogus())
        {
            return setToBogus();
        }

        if (other.fBytes != NULL)
        {
            ensureCapacity(other.fCount);

            if (isBogus())
            {
                return *this;
            }

            fHashCode = other.fHashCode;
            uprv_memcpy(fBytes, other.fBytes, fCount);
        }
        else
        {
            fCount = 0;
            fBogus = FALSE;
            fHashCode = kEmptyHashCode;
        }
    }

    return *this;
}
StatusWith<std::unique_ptr<CollatorInterface>> CollatorFactoryICU::makeFromBSON(
    const BSONObj& spec) {
    // Parse the locale ID out of the spec.
    auto parsedLocaleID = parseLocaleID(spec);
    if (!parsedLocaleID.isOK()) {
        return parsedLocaleID.getStatus();
    }

    // If spec = {locale: "simple"}, return a null pointer. A null CollatorInterface indicates
    // simple binary compare.
    if (parsedLocaleID.getValue() == CollationSpec::kSimpleBinaryComparison) {
        if (spec.nFields() > 1) {
            return {ErrorCodes::FailedToParse,
                    str::stream() << "If " << CollationSpec::kLocaleField << "="
                                  << CollationSpec::kSimpleBinaryComparison
                                  << ", no other fields should be present in: " << spec};
        }
        return {nullptr};
    }

    // Construct an icu::Locale.
    auto userLocale = icu::Locale::createFromName(parsedLocaleID.getValue().c_str());
    if (userLocale.isBogus()) {
        return {ErrorCodes::BadValue,
                str::stream() << "Field '" << CollationSpec::kLocaleField
                              << "' is not valid in: " << spec};
    }

    // Construct an icu::Collator.
    UErrorCode status = U_ZERO_ERROR;
    std::unique_ptr<icu::Collator> icuCollator(icu::Collator::createInstance(userLocale, status));
    if (U_FAILURE(status)) {
        icu::ErrorCode icuError;
        icuError.set(status);
        return {ErrorCodes::OperationFailed,
                str::stream() << "Failed to create collator: " << icuError.errorName()
                              << ". Collation spec: " << spec};
    }

    Status localeValidationStatus = validateLocaleID(spec, parsedLocaleID.getValue(), *icuCollator);
    if (!localeValidationStatus.isOK()) {
        return localeValidationStatus;
    }

    // Construct a CollationSpec using the options provided in spec or the defaults in icuCollator.
    // Use userLocale.getName() for the localeID, since it is canonicalized and includes options.
    auto parsedSpec = parseToCollationSpec(spec, userLocale.getName(), icuCollator.get());
    if (!parsedSpec.isOK()) {
        return parsedSpec.getStatus();
    }

    auto mongoCollator = stdx::make_unique<CollatorInterfaceICU>(std::move(parsedSpec.getValue()),
                                                                 std::move(icuCollator));
    return {std::move(mongoCollator)};
}
/**
 * Generic filter-based scanning code for UCD property UnicodeSets.
 */
void UnicodeSet::applyFilter(UnicodeSet::Filter filter,
                             void* context,
                             int32_t src,
                             UErrorCode &status) {
    // Walk through all Unicode characters, noting the start
    // and end of each range for which filter.contain(c) is
    // true.  Add each range to a set.
    //
    // To improve performance, use the INCLUSIONS set, which
    // encodes information about character ranges that are known
    // to have identical properties. INCLUSIONS contains
    // only the first characters of such ranges.
    //
    // TODO Where possible, instead of scanning over code points,
    // use internal property data to initialize UnicodeSets for
    // those properties.  Scanning code points is slow.
    if (U_FAILURE(status)) return;

    const UnicodeSet* inclusions = getInclusions(src, status);
    if (U_FAILURE(status)) {
        return;
    }

    clear();

    UChar32 startHasProperty = -1;
    int32_t limitRange = inclusions->getRangeCount();

    for (int j=0; j<limitRange; ++j) {
        // get current range
        UChar32 start = inclusions->getRangeStart(j);
        UChar32 end = inclusions->getRangeEnd(j);

        // for all the code points in the range, process
        for (UChar32 ch = start; ch <= end; ++ch) {
            // only add to this UnicodeSet on inflection points --
            // where the hasProperty value changes to false
            if ((*filter)(ch, context)) {
                if (startHasProperty < 0) {
                    startHasProperty = ch;
                }
            } else if (startHasProperty >= 0) {
                add(startHasProperty, ch-1);
                startHasProperty = -1;
            }
        }
    }
    if (startHasProperty >= 0) {
        add((UChar32)startHasProperty, (UChar32)0x10FFFF);
    }
    if (isBogus() && U_SUCCESS(status)) {
        // We likely ran out of memory. AHHH!
        status = U_MEMORY_ALLOCATION_ERROR;
    }
}
Exemple #4
0
UnicodeSet& UnicodeSet::closeOver(int32_t attribute) {
    if (isFrozen() || isBogus()) {
        return *this;
    }
    if (attribute & (USET_CASE_INSENSITIVE | USET_ADD_CASE_MAPPINGS)) {
        const UCaseProps *csp = ucase_getSingleton();
        {
            UnicodeSet foldSet(*this);
            UnicodeString str;
            USetAdder sa = {
                foldSet.toUSet(),
                _set_add,
                _set_addRange,
                _set_addString,
                NULL, // don't need remove()
                NULL // don't need removeRange()
            };

            // start with input set to guarantee inclusion
            // USET_CASE: remove strings because the strings will actually be reduced (folded);
            //            therefore, start with no strings and add only those needed
            if (attribute & USET_CASE_INSENSITIVE) {
                foldSet.strings->removeAllElements();
            }

            int32_t n = getRangeCount();
            UChar32 result;
            const UChar *full;
            int32_t locCache = 0;

            for (int32_t i=0; i<n; ++i) {
                UChar32 start = getRangeStart(i);
                UChar32 end   = getRangeEnd(i);

                if (attribute & USET_CASE_INSENSITIVE) {
                    // full case closure
                    for (UChar32 cp=start; cp<=end; ++cp) {
                        ucase_addCaseClosure(csp, cp, &sa);
                    }
                } else {
                    // add case mappings
                    // (does not add long s for regular s, or Kelvin for k, for example)
                    for (UChar32 cp=start; cp<=end; ++cp) {
                        result = ucase_toFullLower(csp, cp, NULL, NULL, &full, "", &locCache);
                        addCaseMapping(foldSet, result, full, str);

                        result = ucase_toFullTitle(csp, cp, NULL, NULL, &full, "", &locCache);
                        addCaseMapping(foldSet, result, full, str);

                        result = ucase_toFullUpper(csp, cp, NULL, NULL, &full, "", &locCache);
                        addCaseMapping(foldSet, result, full, str);

                        result = ucase_toFullFolding(csp, cp, &full, 0);
                        addCaseMapping(foldSet, result, full, str);
                    }
                }
            }
            if (strings != NULL && strings->size() > 0) {
                if (attribute & USET_CASE_INSENSITIVE) {
                    for (int32_t j=0; j<strings->size(); ++j) {
                        str = *(const UnicodeString *) strings->elementAt(j);
                        str.foldCase();
                        if(!ucase_addStringCaseClosure(csp, str.getBuffer(), str.length(), &sa)) {
                            foldSet.add(str); // does not map to code points: add the folded string itself
                        }
                    }
                } else {
                    Locale root("");
#if !UCONFIG_NO_BREAK_ITERATION
                    UErrorCode status = U_ZERO_ERROR;
                    BreakIterator *bi = BreakIterator::createWordInstance(root, status);
                    if (U_SUCCESS(status)) {
#endif
                        const UnicodeString *pStr;

                        for (int32_t j=0; j<strings->size(); ++j) {
                            pStr = (const UnicodeString *) strings->elementAt(j);
                            (str = *pStr).toLower(root);
                            foldSet.add(str);
#if !UCONFIG_NO_BREAK_ITERATION
                            (str = *pStr).toTitle(bi, root);
                            foldSet.add(str);
#endif
                            (str = *pStr).toUpper(root);
                            foldSet.add(str);
                            (str = *pStr).foldCase();
                            foldSet.add(str);
                        }
#if !UCONFIG_NO_BREAK_ITERATION
                    }
                    delete bi;
#endif
                }
            }
            *this = foldSet;
        }
    }
    return *this;
}
Exemple #5
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UnicodeSet&
UnicodeSet::applyPropertyAlias(const UnicodeString& prop,
                               const UnicodeString& value,
                               UErrorCode& ec) {
    if (U_FAILURE(ec) || isFrozen()) return *this;

    // prop and value used to be converted to char * using the default
    // converter instead of the invariant conversion.
    // This should not be necessary because all Unicode property and value
    // names use only invariant characters.
    // If there are any variant characters, then we won't find them anyway.
    // Checking first avoids assertion failures in the conversion.
    if( !uprv_isInvariantUString(prop.getBuffer(), prop.length()) ||
        !uprv_isInvariantUString(value.getBuffer(), value.length())
    ) {
        FAIL(ec);
    }
    CharString pname, vname;
    pname.appendInvariantChars(prop, ec);
    vname.appendInvariantChars(value, ec);
    if (U_FAILURE(ec)) return *this;

    UProperty p;
    int32_t v;
    UBool mustNotBeEmpty = FALSE, invert = FALSE;

    if (value.length() > 0) {
        p = u_getPropertyEnum(pname.data());
        if (p == UCHAR_INVALID_CODE) FAIL(ec);

        // Treat gc as gcm
        if (p == UCHAR_GENERAL_CATEGORY) {
            p = UCHAR_GENERAL_CATEGORY_MASK;
        }

        if ((p >= UCHAR_BINARY_START && p < UCHAR_BINARY_LIMIT) ||
            (p >= UCHAR_INT_START && p < UCHAR_INT_LIMIT) ||
            (p >= UCHAR_MASK_START && p < UCHAR_MASK_LIMIT)) {
            v = u_getPropertyValueEnum(p, vname.data());
            if (v == UCHAR_INVALID_CODE) {
                // Handle numeric CCC
                if (p == UCHAR_CANONICAL_COMBINING_CLASS ||
                    p == UCHAR_TRAIL_CANONICAL_COMBINING_CLASS ||
                    p == UCHAR_LEAD_CANONICAL_COMBINING_CLASS) {
                    char* end;
                    double value = uprv_strtod(vname.data(), &end);
                    v = (int32_t) value;
                    if (v != value || v < 0 || *end != 0) {
                        // non-integral or negative value, or trailing junk
                        FAIL(ec);
                    }
                    // If the resultant set is empty then the numeric value
                    // was invalid.
                    mustNotBeEmpty = TRUE;
                } else {
                    FAIL(ec);
                }
            }
        }

        else {

            switch (p) {
            case UCHAR_NUMERIC_VALUE:
                {
                    char* end;
                    double value = uprv_strtod(vname.data(), &end);
                    if (*end != 0) {
                        FAIL(ec);
                    }
                    applyFilter(numericValueFilter, &value, UPROPS_SRC_CHAR, ec);
                    return *this;
                }
            case UCHAR_NAME:
                {
                    // Must munge name, since u_charFromName() does not do
                    // 'loose' matching.
                    char buf[128]; // it suffices that this be > uprv_getMaxCharNameLength
                    if (!mungeCharName(buf, vname.data(), sizeof(buf))) FAIL(ec);
                    UChar32 ch = u_charFromName(U_EXTENDED_CHAR_NAME, buf, &ec);
                    if (U_SUCCESS(ec)) {
                        clear();
                        add(ch);
                        return *this;
                    } else {
                        FAIL(ec);
                    }
                }
            case UCHAR_UNICODE_1_NAME:
                // ICU 49 deprecates the Unicode_1_Name property APIs.
                FAIL(ec);
            case UCHAR_AGE:
                {
                    // Must munge name, since u_versionFromString() does not do
                    // 'loose' matching.
                    char buf[128];
                    if (!mungeCharName(buf, vname.data(), sizeof(buf))) FAIL(ec);
                    UVersionInfo version;
                    u_versionFromString(version, buf);
                    applyFilter(versionFilter, &version, UPROPS_SRC_PROPSVEC, ec);
                    return *this;
                }
            case UCHAR_SCRIPT_EXTENSIONS:
                v = u_getPropertyValueEnum(UCHAR_SCRIPT, vname.data());
                if (v == UCHAR_INVALID_CODE) {
                    FAIL(ec);
                }
                // fall through to calling applyIntPropertyValue()
                break;
            default:
                // p is a non-binary, non-enumerated property that we
                // don't support (yet).
                FAIL(ec);
            }
        }
    }

    else {
        // value is empty.  Interpret as General Category, Script, or
        // Binary property.
        p = UCHAR_GENERAL_CATEGORY_MASK;
        v = u_getPropertyValueEnum(p, pname.data());
        if (v == UCHAR_INVALID_CODE) {
            p = UCHAR_SCRIPT;
            v = u_getPropertyValueEnum(p, pname.data());
            if (v == UCHAR_INVALID_CODE) {
                p = u_getPropertyEnum(pname.data());
                if (p >= UCHAR_BINARY_START && p < UCHAR_BINARY_LIMIT) {
                    v = 1;
                } else if (0 == uprv_comparePropertyNames(ANY, pname.data())) {
                    set(MIN_VALUE, MAX_VALUE);
                    return *this;
                } else if (0 == uprv_comparePropertyNames(ASCII, pname.data())) {
                    set(0, 0x7F);
                    return *this;
                } else if (0 == uprv_comparePropertyNames(ASSIGNED, pname.data())) {
                    // [:Assigned:]=[:^Cn:]
                    p = UCHAR_GENERAL_CATEGORY_MASK;
                    v = U_GC_CN_MASK;
                    invert = TRUE;
                } else {
                    FAIL(ec);
                }
            }
        }
    }

    applyIntPropertyValue(p, v, ec);
    if(invert) {
        complement();
    }

    if (U_SUCCESS(ec) && (mustNotBeEmpty && isEmpty())) {
        // mustNotBeEmpty is set to true if an empty set indicates
        // invalid input.
        ec = U_ILLEGAL_ARGUMENT_ERROR;
    }

    if (isBogus() && U_SUCCESS(ec)) {
        // We likely ran out of memory. AHHH!
        ec = U_MEMORY_ALLOCATION_ERROR;
    }
    return *this;
}
Exemple #6
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/**
 * Parse the pattern from the given RuleCharacterIterator.  The
 * iterator is advanced over the parsed pattern.
 * @param chars iterator over the pattern characters.  Upon return
 * it will be advanced to the first character after the parsed
 * pattern, or the end of the iteration if all characters are
 * parsed.
 * @param symbols symbol table to use to parse and dereference
 * variables, or null if none.
 * @param rebuiltPat the pattern that was parsed, rebuilt or
 * copied from the input pattern, as appropriate.
 * @param options a bit mask of zero or more of the following:
 * IGNORE_SPACE, CASE.
 */
void UnicodeSet::applyPattern(RuleCharacterIterator& chars,
                              const SymbolTable* symbols,
                              UnicodeString& rebuiltPat,
                              uint32_t options,
                              UnicodeSet& (UnicodeSet::*caseClosure)(int32_t attribute),
                              UErrorCode& ec) {
    if (U_FAILURE(ec)) return;

    // Syntax characters: [ ] ^ - & { }

    // Recognized special forms for chars, sets: c-c s-s s&s

    int32_t opts = RuleCharacterIterator::PARSE_VARIABLES |
                   RuleCharacterIterator::PARSE_ESCAPES;
    if ((options & USET_IGNORE_SPACE) != 0) {
        opts |= RuleCharacterIterator::SKIP_WHITESPACE;
    }

    UnicodeString patLocal, buf;
    UBool usePat = FALSE;
    UnicodeSetPointer scratch;
    RuleCharacterIterator::Pos backup;

    // mode: 0=before [, 1=between [...], 2=after ]
    // lastItem: 0=none, 1=char, 2=set
    int8_t lastItem = 0, mode = 0;
    UChar32 lastChar = 0;
    UChar op = 0;

    UBool invert = FALSE;

    clear();

    while (mode != 2 && !chars.atEnd()) {
        U_ASSERT((lastItem == 0 && op == 0) ||
                 (lastItem == 1 && (op == 0 || op == HYPHEN /*'-'*/)) ||
                 (lastItem == 2 && (op == 0 || op == HYPHEN /*'-'*/ ||
                                    op == INTERSECTION /*'&'*/)));

        UChar32 c = 0;
        UBool literal = FALSE;
        UnicodeSet* nested = 0; // alias - do not delete

        // -------- Check for property pattern

        // setMode: 0=none, 1=unicodeset, 2=propertypat, 3=preparsed
        int8_t setMode = 0;
        if (resemblesPropertyPattern(chars, opts)) {
            setMode = 2;
        }

        // -------- Parse '[' of opening delimiter OR nested set.
        // If there is a nested set, use `setMode' to define how
        // the set should be parsed.  If the '[' is part of the
        // opening delimiter for this pattern, parse special
        // strings "[", "[^", "[-", and "[^-".  Check for stand-in
        // characters representing a nested set in the symbol
        // table.

        else {
            // Prepare to backup if necessary
            chars.getPos(backup);
            c = chars.next(opts, literal, ec);
            if (U_FAILURE(ec)) return;

            if (c == 0x5B /*'['*/ && !literal) {
                if (mode == 1) {
                    chars.setPos(backup); // backup
                    setMode = 1;
                } else {
                    // Handle opening '[' delimiter
                    mode = 1;
                    patLocal.append((UChar) 0x5B /*'['*/);
                    chars.getPos(backup); // prepare to backup
                    c = chars.next(opts, literal, ec); 
                    if (U_FAILURE(ec)) return;
                    if (c == 0x5E /*'^'*/ && !literal) {
                        invert = TRUE;
                        patLocal.append((UChar) 0x5E /*'^'*/);
                        chars.getPos(backup); // prepare to backup
                        c = chars.next(opts, literal, ec);
                        if (U_FAILURE(ec)) return;
                    }
                    // Fall through to handle special leading '-';
                    // otherwise restart loop for nested [], \p{}, etc.
                    if (c == HYPHEN /*'-'*/) {
                        literal = TRUE;
                        // Fall through to handle literal '-' below
                    } else {
                        chars.setPos(backup); // backup
                        continue;
                    }
                }
            } else if (symbols != 0) {
                const UnicodeFunctor *m = symbols->lookupMatcher(c);
                if (m != 0) {
                    const UnicodeSet *ms = dynamic_cast<const UnicodeSet *>(m);
                    if (ms == NULL) {
                        ec = U_MALFORMED_SET;
                        return;
                    }
                    // casting away const, but `nested' won't be modified
                    // (important not to modify stored set)
                    nested = const_cast<UnicodeSet*>(ms);
                    setMode = 3;
                }
            }
        }

        // -------- Handle a nested set.  This either is inline in
        // the pattern or represented by a stand-in that has
        // previously been parsed and was looked up in the symbol
        // table.

        if (setMode != 0) {
            if (lastItem == 1) {
                if (op != 0) {
                    // syntaxError(chars, "Char expected after operator");
                    ec = U_MALFORMED_SET;
                    return;
                }
                add(lastChar, lastChar);
                _appendToPat(patLocal, lastChar, FALSE);
                lastItem = 0;
                op = 0;
            }

            if (op == HYPHEN /*'-'*/ || op == INTERSECTION /*'&'*/) {
                patLocal.append(op);
            }

            if (nested == 0) {
                // lazy allocation
                if (!scratch.allocate()) {
                    ec = U_MEMORY_ALLOCATION_ERROR;
                    return;
                }
                nested = scratch.pointer();
            }
            switch (setMode) {
            case 1:
                nested->applyPattern(chars, symbols, patLocal, options, caseClosure, ec);
                break;
            case 2:
                chars.skipIgnored(opts);
                nested->applyPropertyPattern(chars, patLocal, ec);
                if (U_FAILURE(ec)) return;
                break;
            case 3: // `nested' already parsed
                nested->_toPattern(patLocal, FALSE);
                break;
            }

            usePat = TRUE;

            if (mode == 0) {
                // Entire pattern is a category; leave parse loop
                *this = *nested;
                mode = 2;
                break;
            }

            switch (op) {
            case HYPHEN: /*'-'*/
                removeAll(*nested);
                break;
            case INTERSECTION: /*'&'*/
                retainAll(*nested);
                break;
            case 0:
                addAll(*nested);
                break;
            }

            op = 0;
            lastItem = 2;

            continue;
        }

        if (mode == 0) {
            // syntaxError(chars, "Missing '['");
            ec = U_MALFORMED_SET;
            return;
        }

        // -------- Parse special (syntax) characters.  If the
        // current character is not special, or if it is escaped,
        // then fall through and handle it below.

        if (!literal) {
            switch (c) {
            case 0x5D /*']'*/:
                if (lastItem == 1) {
                    add(lastChar, lastChar);
                    _appendToPat(patLocal, lastChar, FALSE);
                }
                // Treat final trailing '-' as a literal
                if (op == HYPHEN /*'-'*/) {
                    add(op, op);
                    patLocal.append(op);
                } else if (op == INTERSECTION /*'&'*/) {
                    // syntaxError(chars, "Trailing '&'");
                    ec = U_MALFORMED_SET;
                    return;
                }
                patLocal.append((UChar) 0x5D /*']'*/);
                mode = 2;
                continue;
            case HYPHEN /*'-'*/:
                if (op == 0) {
                    if (lastItem != 0) {
                        op = (UChar) c;
                        continue;
                    } else {
                        // Treat final trailing '-' as a literal
                        add(c, c);
                        c = chars.next(opts, literal, ec);
                        if (U_FAILURE(ec)) return;
                        if (c == 0x5D /*']'*/ && !literal) {
                            patLocal.append(HYPHEN_RIGHT_BRACE, 2);
                            mode = 2;
                            continue;
                        }
                    }
                }
                // syntaxError(chars, "'-' not after char or set");
                ec = U_MALFORMED_SET;
                return;
            case INTERSECTION /*'&'*/:
                if (lastItem == 2 && op == 0) {
                    op = (UChar) c;
                    continue;
                }
                // syntaxError(chars, "'&' not after set");
                ec = U_MALFORMED_SET;
                return;
            case 0x5E /*'^'*/:
                // syntaxError(chars, "'^' not after '['");
                ec = U_MALFORMED_SET;
                return;
            case 0x7B /*'{'*/:
                if (op != 0) {
                    // syntaxError(chars, "Missing operand after operator");
                    ec = U_MALFORMED_SET;
                    return;
                }
                if (lastItem == 1) {
                    add(lastChar, lastChar);
                    _appendToPat(patLocal, lastChar, FALSE);
                }
                lastItem = 0;
                buf.truncate(0);
                {
                    UBool ok = FALSE;
                    while (!chars.atEnd()) {
                        c = chars.next(opts, literal, ec);
                        if (U_FAILURE(ec)) return;
                        if (c == 0x7D /*'}'*/ && !literal) {
                            ok = TRUE;
                            break;
                        }
                        buf.append(c);
                    }
                    if (buf.length() < 1 || !ok) {
                        // syntaxError(chars, "Invalid multicharacter string");
                        ec = U_MALFORMED_SET;
                        return;
                    }
                }
                // We have new string. Add it to set and continue;
                // we don't need to drop through to the further
                // processing
                add(buf);
                patLocal.append((UChar) 0x7B /*'{'*/);
                _appendToPat(patLocal, buf, FALSE);
                patLocal.append((UChar) 0x7D /*'}'*/);
                continue;
            case SymbolTable::SYMBOL_REF:
                //         symbols  nosymbols
                // [a-$]   error    error (ambiguous)
                // [a$]    anchor   anchor
                // [a-$x]  var "x"* literal '$'
                // [a-$.]  error    literal '$'
                // *We won't get here in the case of var "x"
                {
                    chars.getPos(backup);
                    c = chars.next(opts, literal, ec);
                    if (U_FAILURE(ec)) return;
                    UBool anchor = (c == 0x5D /*']'*/ && !literal);
                    if (symbols == 0 && !anchor) {
                        c = SymbolTable::SYMBOL_REF;
                        chars.setPos(backup);
                        break; // literal '$'
                    }
                    if (anchor && op == 0) {
                        if (lastItem == 1) {
                            add(lastChar, lastChar);
                            _appendToPat(patLocal, lastChar, FALSE);
                        }
                        add(U_ETHER);
                        usePat = TRUE;
                        patLocal.append((UChar) SymbolTable::SYMBOL_REF);
                        patLocal.append((UChar) 0x5D /*']'*/);
                        mode = 2;
                        continue;
                    }
                    // syntaxError(chars, "Unquoted '$'");
                    ec = U_MALFORMED_SET;
                    return;
                }
            default:
                break;
            }
        }

        // -------- Parse literal characters.  This includes both
        // escaped chars ("\u4E01") and non-syntax characters
        // ("a").

        switch (lastItem) {
        case 0:
            lastItem = 1;
            lastChar = c;
            break;
        case 1:
            if (op == HYPHEN /*'-'*/) {
                if (lastChar >= c) {
                    // Don't allow redundant (a-a) or empty (b-a) ranges;
                    // these are most likely typos.
                    // syntaxError(chars, "Invalid range");
                    ec = U_MALFORMED_SET;
                    return;
                }
                add(lastChar, c);
                _appendToPat(patLocal, lastChar, FALSE);
                patLocal.append(op);
                _appendToPat(patLocal, c, FALSE);
                lastItem = 0;
                op = 0;
            } else {
                add(lastChar, lastChar);
                _appendToPat(patLocal, lastChar, FALSE);
                lastChar = c;
            }
            break;
        case 2:
            if (op != 0) {
                // syntaxError(chars, "Set expected after operator");
                ec = U_MALFORMED_SET;
                return;
            }
            lastChar = c;
            lastItem = 1;
            break;
        }
    }

    if (mode != 2) {
        // syntaxError(chars, "Missing ']'");
        ec = U_MALFORMED_SET;
        return;
    }

    chars.skipIgnored(opts);

    /**
     * Handle global flags (invert, case insensitivity).  If this
     * pattern should be compiled case-insensitive, then we need
     * to close over case BEFORE COMPLEMENTING.  This makes
     * patterns like /[^abc]/i work.
     */
    if ((options & USET_CASE_INSENSITIVE) != 0) {
        (this->*caseClosure)(USET_CASE_INSENSITIVE);
    }
    else if ((options & USET_ADD_CASE_MAPPINGS) != 0) {
        (this->*caseClosure)(USET_ADD_CASE_MAPPINGS);
    }
    if (invert) {
        complement();
    }

    // Use the rebuilt pattern (patLocal) only if necessary.  Prefer the
    // generated pattern.
    if (usePat) {
        rebuiltPat.append(patLocal);
    } else {
        _generatePattern(rebuiltPat, FALSE);
    }
    if (isBogus() && U_SUCCESS(ec)) {
        // We likely ran out of memory. AHHH!
        ec = U_MEMORY_ALLOCATION_ERROR;
    }
}