C++ (Cpp) _extractSign Examples

Example #1

File: parse_number.cpp Project: Albert-B-P/mongo

    Status parseNumberFromStringWithBase(
            const StringData& stringValue, int base, NumberType* result) {

        typedef ::std::numeric_limits<NumberType> limits;

        if (base == 1 || base < 0 || base > 36)
            return Status(ErrorCodes::BadValue, "Invalid base", 0);

        bool isNegative = false;
        StringData str = _extractBase(_extractSign(stringValue, &isNegative), base, &base);

        if (str.empty())
            return Status(ErrorCodes::FailedToParse, "No digits");

        NumberType n(0);
        if (isNegative) {
            if (limits::is_signed) {
                for (size_t i = 0; i < str.size(); ++i) {
                    NumberType digitValue = NumberType(_digitValue(str[i]));
                    if (int(digitValue) >= base)
                        return Status(ErrorCodes::FailedToParse, "Bad digit");

// MSVC: warning C4146: unary minus operator applied to unsigned type, result still unsigned
// This code is statically known to be dead when NumberType is unsigned, so the warning is not real
#pragma warning(push)
#pragma warning(disable:4146)
                    if ((NumberType(limits::min() / base) > n) ||
                        ((limits::min() - NumberType(n * base)) > -digitValue)) {
#pragma warning(pop)

                        return Status(ErrorCodes::FailedToParse, "Underflow");
                    }

                    n *= NumberType(base);
                    n -= NumberType(digitValue);
                }
            }
            else {
                return Status(ErrorCodes::FailedToParse, "Negative value");
            }
        }
        else {
            for (size_t i = 0; i < str.size(); ++i) {
                NumberType digitValue = NumberType(_digitValue(str[i]));
                if (int(digitValue) >= base)
                    return Status(ErrorCodes::FailedToParse, "Bad digit");
                if ((NumberType(limits::max() / base) < n) ||
                    (NumberType(limits::max() - n * base) < digitValue)) {

                    return Status(ErrorCodes::FailedToParse, "Overflow");
                }

                n *= NumberType(base);
                n += NumberType(digitValue);
            }
        }
        *result = n;
        return Status::OK();
    }

Example #2

File: parse_number.cpp Project: KevinEtienne/mongo

    Status parseNumberFromStringWithBase(
            const StringData& stringValue, int base, NumberType* result) {

        typedef ::std::numeric_limits<NumberType> limits;

        if (base == 1 || base < 0 || base > 36)
            return Status(ErrorCodes::BadValue, "Invalid base", 0);

        if (stringValue.size() == 0)
            return Status(ErrorCodes::FailedToParse, "Empty string");

        bool isNegative = false;
        StringData str = _extractBase(_extractSign(stringValue, &isNegative), base, &base);

        NumberType n(0);
        if (isNegative) {
            if (limits::is_signed) {
                for (size_t i = 0; i < str.size(); ++i) {
                    NumberType digitValue = NumberType(_digitValue(str[i]));
                    if (int(digitValue) >= base)
                        return Status(ErrorCodes::FailedToParse, "Bad digit");
                    if ((NumberType(limits::min() / base) > n) ||
                        ((limits::min() - NumberType(n * base)) > -digitValue)) {

                        return Status(ErrorCodes::FailedToParse, "Underflow");
                    }

                    n *= NumberType(base);
                    n -= NumberType(digitValue);
                }
            }
            else {
                return Status(ErrorCodes::FailedToParse, "Negative value");
            }
        }
        else {
            for (size_t i = 0; i < str.size(); ++i) {
                NumberType digitValue = NumberType(_digitValue(str[i]));
                if (int(digitValue) >= base)
                    return Status(ErrorCodes::FailedToParse, "Bad digit");
                if ((NumberType(limits::max() / base) < n) ||
                    (NumberType(limits::max() - n * base) < digitValue)) {

                    return Status(ErrorCodes::FailedToParse, "Overflow");
                }

                n *= NumberType(base);
                n += NumberType(digitValue);
            }
        }
        *result = n;
        return Status::OK();
    }