ClickHouse/dbms/src/Functions/FunctionsCoding.h

#pragma once

#include <Common/hex.h>
#include <IO/ReadBufferFromString.h>
#include <IO/WriteHelpers.h>
#include <DataTypes/DataTypesNumber.h>
#include <DataTypes/DataTypeString.h>
#include <DataTypes/DataTypeFixedString.h>
#include <DataTypes/DataTypeArray.h>
#include <DataTypes/DataTypeDate.h>
#include <DataTypes/DataTypeDateTime.h>
#include <Columns/ColumnsNumber.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnFixedString.h>
#include <Columns/ColumnArray.h>
#include <Columns/ColumnConst.h>
#include <Functions/IFunction.h>

#include <arpa/inet.h>
#include <ext/range.h>
#include <array>


namespace DB
{

namespace ErrorCodes
{
    extern const int TOO_LESS_ARGUMENTS_FOR_FUNCTION;
}


/** Encoding functions:
  *
  * IPv4NumToString (num) - See below.
  * IPv4StringToNum(string) - Convert, for example, '192.168.0.1' to 3232235521 and vice versa.
  *
  * hex(x) - Returns hex; capital letters; there are no prefixes 0x or suffixes h.
  *          For numbers, returns a variable-length string - hex in the "human" (big endian) format, with the leading zeros being cut,
  *          but only by whole bytes. For dates and datetimes - the same as for numbers.
  *          For example, hex(257) = '0101'.
  * unhex(string) - Returns a string, hex of which is equal to `string` with regard of case and discarding one leading zero.
  *                 If such a string does not exist, could return arbitary implementation specific value.
  *
  * bitmaskToArray(x) - Returns an array of powers of two in the binary form of x. For example, bitmaskToArray(50) = [2, 16, 32].
  */


constexpr auto ipv4_bytes_length = 4;
constexpr auto ipv6_bytes_length = 16;
constexpr auto uuid_bytes_length = 16;
constexpr auto uuid_text_length = 36;

class IPv6Format
{
private:
    /// integer logarithm, return ceil(log(value, base)) (the smallest integer greater or equal  than log(value, base)
    static constexpr uint32_t int_log(const uint32_t value, const uint32_t base, const bool carry = false)
    {
        return value >= base ? 1 + int_log(value / base, base, value % base || carry) : value % base > 1 || carry;
    }

    /// print integer in desired base, faster than sprintf
    template <uint32_t base, typename T, uint32_t buffer_size = sizeof(T) * int_log(256, base, false)>
    static void print_integer(char *& out, T value)
    {
        if (value == 0)
            *out++ = '0';
        else
        {
            char buf[buffer_size];
            auto ptr = buf;

            while (value > 0)
            {
                *ptr++ = hexLowercase(value % base);
                value /= base;
            }

            while (ptr != buf)
                *out++ = *--ptr;
        }
    }

    /// print IPv4 address as %u.%u.%u.%u
    static void ipv4_format(const unsigned char * src, char *& dst, UInt8 zeroed_tail_bytes_count)
    {
        const auto limit = ipv4_bytes_length - zeroed_tail_bytes_count;

        for (const auto i : ext::range(0, ipv4_bytes_length))
        {
            UInt8 byte = (i < limit) ? src[i] : 0;
            print_integer<10, UInt8>(dst, byte);

            if (i != ipv4_bytes_length - 1)
                *dst++ = '.';
        }
    }

public:
    /** rewritten inet_ntop6 from http://svn.apache.org/repos/asf/apr/apr/trunk/network_io/unix/inet_pton.c
     *    performs significantly faster than the reference implementation due to the absence of sprintf calls,
     *    bounds checking, unnecessary string copying and length calculation
     */
    static const void apply(const unsigned char * src, char *& dst, UInt8 zeroed_tail_bytes_count = 0)
    {
        struct { int base, len; } best{-1}, cur{-1};
        std::array<uint16_t, ipv6_bytes_length / sizeof(uint16_t)> words{};

        /** Preprocess:
         *    Copy the input (bytewise) array into a wordwise array.
         *    Find the longest run of 0x00's in src[] for :: shorthanding. */
        for (const auto i : ext::range(0, ipv6_bytes_length - zeroed_tail_bytes_count))
            words[i / 2] |= src[i] << ((1 - (i % 2)) << 3);

        for (const auto i : ext::range(0, words.size()))
        {
            if (words[i] == 0) {
                if (cur.base == -1)
                    cur.base = i, cur.len = 1;
                else
                    cur.len++;
            }
            else
            {
                if (cur.base != -1)
                {
                    if (best.base == -1 || cur.len > best.len)
                        best = cur;
                    cur.base = -1;
                }
            }
        }

        if (cur.base != -1)
        {
            if (best.base == -1 || cur.len > best.len)
                best = cur;
        }

        if (best.base != -1 && best.len < 2)
            best.base = -1;

        /// Format the result.
        for (const int i : ext::range(0, words.size()))
        {
            /// Are we inside the best run of 0x00's?
            if (best.base != -1 && i >= best.base && i < (best.base + best.len))
            {
                if (i == best.base)
                    *dst++ = ':';
                continue;
            }

            /// Are we following an initial run of 0x00s or any real hex?
            if (i != 0)
                *dst++ = ':';

            /// Is this address an encapsulated IPv4?
            if (i == 6 && best.base == 0 && (best.len == 6 || (best.len == 5 && words[5] == 0xffffu)))
            {
                ipv4_format(src + 12, dst, std::min(zeroed_tail_bytes_count, static_cast<UInt8>(ipv4_bytes_length)));
                break;
            }

            print_integer<16>(dst, words[i]);
        }

        /// Was it a trailing run of 0x00's?
        if (best.base != -1 && (best.base + best.len) == words.size())
            *dst++ = ':';

        *dst++ = '\0';
    }
};


class FunctionIPv6NumToString : public IFunction
{
public:
    static constexpr auto name = "IPv6NumToString";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv6NumToString>(); }

    String getName() const override { return name; }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        const auto ptr = typeid_cast<const DataTypeFixedString *>(arguments[0].get());
        if (!ptr || ptr->getN() != ipv6_bytes_length)
            throw Exception("Illegal type " + arguments[0]->getName() +
                            " of argument of function " + getName() +
                            ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, const size_t result) override
    {
        const auto & col_type_name = block.safeGetByPosition(arguments[0]);
        const ColumnPtr & column = col_type_name.column;

        if (const auto col_in = typeid_cast<const ColumnFixedString *>(column.get()))
        {
            if (col_in->getN() != ipv6_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto size = col_in->size();
            const auto & vec_in = col_in->getChars();

            auto col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();
            vec_res.resize(size * INET6_ADDRSTRLEN);
            offsets_res.resize(size);

            auto begin = reinterpret_cast<char *>(&vec_res[0]);
            auto pos = begin;

            for (size_t offset = 0, i = 0; offset < vec_in.size(); offset += ipv6_bytes_length, ++i)
            {
                IPv6Format::apply(&vec_in[offset], pos);
                offsets_res[i] = pos - begin;
            }

            vec_res.resize(pos - begin);
        }
        else if (const auto col_in = typeid_cast<const ColumnConst<String> *>(column.get()))
        {
            const auto data_type_fixed_string = typeid_cast<const DataTypeFixedString *>(col_in->getDataType().get());
            if (!data_type_fixed_string || data_type_fixed_string->getN() != ipv6_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto & data_in = col_in->getData();

            char buf[INET6_ADDRSTRLEN];
            char * dst = buf;
            IPv6Format::apply(reinterpret_cast<const unsigned char *>(data_in.data()), dst);

            block.safeGetByPosition(result).column = std::make_shared<ColumnConstString>(col_in->size(), buf);
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionCutIPv6 : public IFunction
{
public:
    static constexpr auto name = "cutIPv6";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionCutIPv6>(); }

    String getName() const override { return name; }

    size_t getNumberOfArguments() const override { return 3; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        const auto ptr = typeid_cast<const DataTypeFixedString *>(arguments[0].get());
        if (!ptr || ptr->getN() != ipv6_bytes_length)
            throw Exception("Illegal type " + arguments[0]->getName() +
                            " of argument 1 of function " + getName() +
                            ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        if (!typeid_cast<const DataTypeUInt8 *>(arguments[1].get()))
            throw Exception("Illegal type " + arguments[1]->getName() +
                            " of argument 2 of function " + getName(),
                            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        if (!typeid_cast<const DataTypeUInt8 *>(arguments[2].get()))
            throw Exception("Illegal type " + arguments[2]->getName() +
                            " of argument 3 of function " + getName(),
                            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, const size_t result) override
    {
        const auto & col_type_name = block.safeGetByPosition(arguments[0]);
        const ColumnPtr & column = col_type_name.column;

        const auto & col_ipv6_zeroed_tail_bytes_type = block.safeGetByPosition(arguments[1]);
        const auto & col_ipv6_zeroed_tail_bytes = col_ipv6_zeroed_tail_bytes_type.column;
        const auto & col_ipv4_zeroed_tail_bytes_type = block.safeGetByPosition(arguments[2]);
        const auto & col_ipv4_zeroed_tail_bytes = col_ipv4_zeroed_tail_bytes_type.column;

        if (const auto col_in = typeid_cast<const ColumnFixedString *>(column.get()))
        {
            if (col_in->getN() != ipv6_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto ipv6_zeroed_tail_bytes = typeid_cast<const ColumnConst<UInt8> *>(col_ipv6_zeroed_tail_bytes.get());
            if (!ipv6_zeroed_tail_bytes)
                throw Exception("Illegal type " + col_ipv6_zeroed_tail_bytes_type.type->getName() +
                                " of argument 2 of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            UInt8 ipv6_zeroed_tail_bytes_count = ipv6_zeroed_tail_bytes->getData();
            if (ipv6_zeroed_tail_bytes_count > ipv6_bytes_length)
                throw Exception("Illegal value for argument 2 " + col_ipv6_zeroed_tail_bytes_type.type->getName() +
                                " of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto ipv4_zeroed_tail_bytes = typeid_cast<const ColumnConst<UInt8> *>(col_ipv4_zeroed_tail_bytes.get());
            if (!ipv4_zeroed_tail_bytes)
                throw Exception("Illegal type " + col_ipv4_zeroed_tail_bytes_type.type->getName() +
                                " of argument 3 of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            UInt8 ipv4_zeroed_tail_bytes_count = ipv4_zeroed_tail_bytes->getData();
            if (ipv4_zeroed_tail_bytes_count > ipv6_bytes_length)
                throw Exception("Illegal value for argument 3 " + col_ipv4_zeroed_tail_bytes_type.type->getName() +
                                " of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto size = col_in->size();
            const auto & vec_in = col_in->getChars();

            auto col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();
            vec_res.resize(size * INET6_ADDRSTRLEN);
            offsets_res.resize(size);

            auto begin = reinterpret_cast<char *>(&vec_res[0]);
            auto pos = begin;

            for (size_t offset = 0, i = 0; offset < vec_in.size(); offset += ipv6_bytes_length, ++i)
            {
                const auto address = &vec_in[offset];
                UInt8 zeroed_tail_bytes_count = isIPv4Mapped(address) ? ipv4_zeroed_tail_bytes_count : ipv6_zeroed_tail_bytes_count;
                cutAddress(address, pos, zeroed_tail_bytes_count);
                offsets_res[i] = pos - begin;
            }

            vec_res.resize(pos - begin);
        }
        else if (const auto col_in = typeid_cast<const ColumnConst<String> *>(column.get()))
        {
            const auto data_type_fixed_string = typeid_cast<const DataTypeFixedString *>(col_in->getDataType().get());
            if (!data_type_fixed_string || data_type_fixed_string->getN() != ipv6_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(ipv6_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto ipv6_zeroed_tail_bytes = typeid_cast<const ColumnConst<UInt8> *>(col_ipv6_zeroed_tail_bytes.get());
            if (!ipv6_zeroed_tail_bytes)
                throw Exception("Illegal type " + col_ipv6_zeroed_tail_bytes_type.type->getName() +
                                " of argument 2 of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            UInt8 ipv6_zeroed_tail_bytes_count = ipv6_zeroed_tail_bytes->getData();
            if (ipv6_zeroed_tail_bytes_count > ipv6_bytes_length)
                throw Exception("Illegal value for argument 2 " + col_ipv6_zeroed_tail_bytes_type.type->getName() +
                                " of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto ipv4_zeroed_tail_bytes = typeid_cast<const ColumnConst<UInt8> *>(col_ipv4_zeroed_tail_bytes.get());
            if (!ipv4_zeroed_tail_bytes)
                throw Exception("Illegal type " + col_ipv4_zeroed_tail_bytes_type.type->getName() +
                                " of argument 3 of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            UInt8 ipv4_zeroed_tail_bytes_count = ipv4_zeroed_tail_bytes->getData();
            if (ipv4_zeroed_tail_bytes_count > ipv6_bytes_length)
                throw Exception("Illegal value for argument 3 " + col_ipv6_zeroed_tail_bytes_type.type->getName() +
                                " of function " + getName(),
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto & data_in = col_in->getData();

            char buf[INET6_ADDRSTRLEN];
            char * dst = buf;

            const auto address = reinterpret_cast<const unsigned char *>(data_in.data());
            UInt8 zeroed_tail_bytes_count = isIPv4Mapped(address) ? ipv4_zeroed_tail_bytes_count : ipv6_zeroed_tail_bytes_count;
            cutAddress(address, dst, zeroed_tail_bytes_count);

            block.safeGetByPosition(result).column = std::make_shared<ColumnConstString>(col_in->size(), buf);
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }

private:
    bool isIPv4Mapped(const unsigned char * address) const
    {
        return (*reinterpret_cast<const UInt64 *>(&address[0]) == 0) &&
            ((*reinterpret_cast<const UInt64 *>(&address[8]) & 0x00000000FFFFFFFFull) == 0x00000000FFFF0000ull);
    }

    void cutAddress(const unsigned char * address, char *& dst, UInt8 zeroed_tail_bytes_count)
    {
        IPv6Format::apply(address, dst, zeroed_tail_bytes_count);
    }
};


class FunctionIPv6StringToNum : public IFunction
{
public:
    static constexpr auto name = "IPv6StringToNum";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv6StringToNum>(); }

    String getName() const override { return name; }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeFixedString>(ipv6_bytes_length);
    }


    static bool ipv4_scan(const char * src, unsigned char * dst)
    {
        constexpr auto size = sizeof(UInt32);
        char bytes[size]{};

        for (const auto i : ext::range(0, size))
        {
            UInt32 value = 0;
            size_t len = 0;
            while (isNumericASCII(*src) && len <= 3)
            {
                value = value * 10 + (*src - '0');
                ++len;
                ++src;
            }

            if (len == 0 || value > 255 || (i < size - 1 && *src != '.'))
            {
                memset(dst, 0, size);
                return false;
            }
            bytes[i] = value;
            ++src;
        }

        if (src[-1] != '\0')
        {
            memset(dst, 0, size);
            return false;
        }

        memcpy(dst, bytes, sizeof(bytes));
        return true;
    }

    /// slightly altered implementation from http://svn.apache.org/repos/asf/apr/apr/trunk/network_io/unix/inet_pton.c
    static void ipv6_scan(const char *  src, unsigned char * dst)
    {
        const auto clear_dst = [dst]
        {
            memset(dst, '\0', ipv6_bytes_length);
        };

        /// Leading :: requires some special handling.
        if (*src == ':')
            if (*++src != ':')
                return clear_dst();

        /// get integer value for a hexademical char digit, or -1
        const auto number_by_char = [] (const char ch)
        {
            if ('A' <= ch && ch <= 'F')
                return 10 + ch - 'A';

            if ('a' <= ch && ch <= 'f')
                return 10 + ch - 'a';

            if ('0' <= ch && ch <= '9')
                return ch - '0';

            return -1;
        };

        unsigned char tmp[ipv6_bytes_length]{};
        auto tp = tmp;
        auto endp = tp + ipv6_bytes_length;
        auto curtok = src;
        auto saw_xdigit = false;
        uint16_t val{};
        unsigned char * colonp = nullptr;

        while (const auto ch = *src++)
        {
            const auto num = number_by_char(ch);

            if (num != -1)
            {
                val <<= 4;
                val |= num;
                if (val > 0xffffu)
                    return clear_dst();

                saw_xdigit = 1;
                continue;
            }

            if (ch == ':')
            {
                curtok = src;
                if (!saw_xdigit)
                {
                    if (colonp)
                        return clear_dst();

                    colonp = tp;
                    continue;
                }

                if (tp + sizeof(uint16_t) > endp)
                    return clear_dst();

                *tp++ = static_cast<unsigned char>((val >> 8) & 0xffu);
                *tp++ = static_cast<unsigned char>(val & 0xffu);
                saw_xdigit = false;
                val = 0;
                continue;
            }

            if (ch == '.' && (tp + ipv4_bytes_length) <= endp)
            {
                if (!ipv4_scan(curtok, tp))
                    return clear_dst();

                tp += ipv4_bytes_length;
                saw_xdigit = false;
                break;    /* '\0' was seen by ipv4_scan(). */
            }

            return clear_dst();
        }

        if (saw_xdigit)
        {
            if (tp + sizeof(uint16_t) > endp)
                return clear_dst();

            *tp++ = static_cast<unsigned char>((val >> 8) & 0xffu);
            *tp++ = static_cast<unsigned char>(val & 0xffu);
        }

        if (colonp)
        {
            /*
             * Since some memmove()'s erroneously fail to handle
             * overlapping regions, we'll do the shift by hand.
             */
            const auto n = tp - colonp;

            for (int i = 1; i <= n; i++)
            {
                endp[- i] = colonp[n - i];
                colonp[n - i] = 0;
            }
            tp = endp;
        }

        if (tp != endp)
            return clear_dst();

        memcpy(dst, tmp, sizeof(tmp));
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const auto col_in = typeid_cast<const ColumnString *>(column.get()))
        {
            const auto col_res = std::make_shared<ColumnFixedString>(ipv6_bytes_length);
            block.safeGetByPosition(result).column = col_res;

            auto & vec_res = col_res->getChars();
            vec_res.resize(col_in->size() * ipv6_bytes_length);

            const ColumnString::Chars_t & vec_src = col_in->getChars();
            const ColumnString::Offsets_t & offsets_src = col_in->getOffsets();
            size_t src_offset = 0;

            for (size_t out_offset = 0, i = 0;
                 out_offset < vec_res.size();
                 out_offset += ipv6_bytes_length, ++i)
            {
                ipv6_scan(reinterpret_cast<const char * >(&vec_src[src_offset]), &vec_res[out_offset]);
                src_offset = offsets_src[i];
            }
        }
        else if (const auto col_in = typeid_cast<const ColumnConstString *>(column.get()))
        {
            String out(ipv6_bytes_length, 0);
            ipv6_scan(col_in->getData().data(), reinterpret_cast<unsigned char *>(&out[0]));

            block.safeGetByPosition(result).column = std::make_shared<ColumnConst<String>>(
                col_in->size(),
                out,
                std::make_shared<DataTypeFixedString>(ipv6_bytes_length));
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
                            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionIPv4NumToString : public IFunction
{
public:
    static constexpr auto name = "IPv4NumToString";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv4NumToString>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeUInt32 *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName() + ", expected UInt32",
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    static void formatIP(UInt32 ip, char *& out)
    {
        char * begin = out;

        /// Write everything backwards.
        for (size_t offset = 0; offset <= 24; offset += 8)
        {
            if (offset > 0)
                *(out++) = '.';

            /// Get the next byte.
            UInt32 value = (ip >> offset) & static_cast<UInt32>(255);

            /// Faster than sprintf.
            if (value == 0)
            {
                *(out++) = '0';
            }
            else
            {
                while (value > 0)
                {
                    *(out++) = '0' + value % 10;
                    value /= 10;
                }
            }
        }

        /// And reverse.
        std::reverse(begin, out);

        *(out++) = '\0';
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnUInt32 * col = typeid_cast<const ColumnUInt32 *>(column.get()))
        {
            const ColumnUInt32::Container_t & vec_in = col->getData();

            std::shared_ptr<ColumnString> col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();

            vec_res.resize(vec_in.size() * INET_ADDRSTRLEN); /// the longest value is: 255.255.255.255\0
            offsets_res.resize(vec_in.size());
            char * begin = reinterpret_cast<char *>(&vec_res[0]);
            char * pos = begin;

            for (size_t i = 0; i < vec_in.size(); ++i)
            {
                formatIP(vec_in[i], pos);
                offsets_res[i] = pos - begin;
            }

            vec_res.resize(pos - begin);
        }
        else if (const ColumnConst<UInt32> * col = typeid_cast<const ColumnConst<UInt32> *>(column.get()))
        {
            char buf[16];
            char * pos = buf;
            formatIP(col->getData(), pos);

            auto col_res = std::make_shared<ColumnConstString>(col->size(), buf);
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionIPv4StringToNum : public IFunction
{
public:
    static constexpr auto name = "IPv4StringToNum";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv4StringToNum>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeUInt32>();
    }

    static UInt32 parseIPv4(const char * pos)
    {
        UInt32 res = 0;
        for (int offset = 24; offset >= 0; offset -= 8)
        {
            UInt32 value = 0;
            size_t len = 0;
            while (isNumericASCII(*pos) && len <= 3)
            {
                value = value * 10 + (*pos - '0');
                ++len;
                ++pos;
            }
            if (len == 0 || value > 255 || (offset > 0 && *pos != '.'))
                return 0;
            res |= value << offset;
            ++pos;
        }
        if (*(pos - 1) != '\0')
            return 0;
        return res;
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnString * col = typeid_cast<const ColumnString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnUInt32>();
            block.safeGetByPosition(result).column = col_res;

            ColumnUInt32::Container_t & vec_res = col_res->getData();
            vec_res.resize(col->size());

            const ColumnString::Chars_t & vec_src = col->getChars();
            const ColumnString::Offsets_t & offsets_src = col->getOffsets();
            size_t prev_offset = 0;

            for (size_t i = 0; i < vec_res.size(); ++i)
            {
                vec_res[i] = parseIPv4(reinterpret_cast<const char *>(&vec_src[prev_offset]));
                prev_offset = offsets_src[i];
            }
        }
        else if (const ColumnConstString * col = typeid_cast<const ColumnConstString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnConst<UInt32>>(col->size(), parseIPv4(col->getData().c_str()));
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
                            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionIPv4NumToStringClassC : public IFunction
{
public:
    static constexpr auto name = "IPv4NumToStringClassC";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv4NumToStringClassC>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeUInt32 *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName() + ", expected UInt32",
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    static void formatIP(UInt32 ip, char *& out)
    {
        char * begin = out;

        for (auto i = 0; i < 3; ++i)
            *(out++) = 'x';

        /// Write everything backwards.
        for (size_t offset = 8; offset <= 24; offset += 8)
        {
            if (offset > 0)
                *(out++) = '.';

            /// Get the next byte.
            UInt32 value = (ip >> offset) & static_cast<UInt32>(255);

            /// Faster than sprintf.
            if (value == 0)
            {
                *(out++) = '0';
            }
            else
            {
                while (value > 0)
                {
                    *(out++) = '0' + value % 10;
                    value /= 10;
                }
            }
        }

        /// And reverse.
        std::reverse(begin, out);

        *(out++) = '\0';
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnUInt32 * col = typeid_cast<const ColumnUInt32 *>(column.get()))
        {
            const ColumnUInt32::Container_t & vec_in = col->getData();

            std::shared_ptr<ColumnString> col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();

            vec_res.resize(vec_in.size() * INET_ADDRSTRLEN); /// the longest value is: 255.255.255.255\0
            offsets_res.resize(vec_in.size());
            char * begin = reinterpret_cast<char *>(&vec_res[0]);
            char * pos = begin;

            for (size_t i = 0; i < vec_in.size(); ++i)
            {
                formatIP(vec_in[i], pos);
                offsets_res[i] = pos - begin;
            }

            vec_res.resize(pos - begin);
        }
        else if (const ColumnConst<UInt32> * col = typeid_cast<const ColumnConst<UInt32> *>(column.get()))
        {
            char buf[16];
            char * pos = buf;
            formatIP(col->getData(), pos);

            auto col_res = std::make_shared<ColumnConstString>(col->size(), buf);
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionIPv4ToIPv6 : public IFunction
{
public:
     static constexpr auto name = "IPv4ToIPv6";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionIPv4ToIPv6>(); }

    String getName() const override { return name; }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (typeid_cast<const DataTypeUInt32 *>(arguments[0].get()) == nullptr)
            throw Exception("Illegal type " + arguments[0]->getName() +
                            " of argument of function " + getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeFixedString>(16);
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, const size_t result) override
    {
        const auto & col_type_name = block.safeGetByPosition(arguments[0]);
        const ColumnPtr & column = col_type_name.column;

        if (const auto col_in = typeid_cast<const ColumnUInt32 *>(column.get()))
        {
            const auto col_res = std::make_shared<ColumnFixedString>(ipv6_bytes_length);
            block.safeGetByPosition(result).column = col_res;

            auto & vec_res = col_res->getChars();
            vec_res.resize(col_in->size() * ipv6_bytes_length);

            const auto & vec_in = col_in->getData();

            for (size_t out_offset = 0, i = 0; out_offset < vec_res.size(); out_offset += ipv6_bytes_length, ++i)
                mapIPv4ToIPv6(vec_in[i], &vec_res[out_offset]);
        }
        else if (const auto col_in = typeid_cast<const ColumnConst<UInt32> *>(column.get()))
        {
            std::string buf;
            buf.resize(ipv6_bytes_length);
            mapIPv4ToIPv6(col_in->getData(), reinterpret_cast<unsigned char *>(&buf[0]));

            auto col_res = std::make_shared<ColumnConstString>(
                ipv6_bytes_length, buf,
                std::make_shared<DataTypeFixedString>(ipv6_bytes_length));
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }

private:
    void mapIPv4ToIPv6(UInt32 in, unsigned char * buf) const
    {
        *reinterpret_cast<UInt64 *>(&buf[0]) = 0;
        *reinterpret_cast<UInt64 *>(&buf[8]) = 0x00000000FFFF0000ull | (static_cast<UInt64>(ntohl(in)) << 32);
    }
};


class FunctionMACNumToString : public IFunction
{
public:
    static constexpr auto name = "MACNumToString";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionMACNumToString>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeUInt64 *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName() + ", expected UInt64",
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    static void formatMAC(UInt64 mac, char *& out)
    {
        char * begin = out;

        /// Write everything backwards.
        for (size_t offset = 0; offset <= 40; offset += 8)
        {
            if (offset > 0)
                *(out++) = ':';

            /// Get the next byte.
            UInt64 value = (mac >> offset) & static_cast<UInt64>(255);

            /// Faster than sprintf.
            if (value < 16)
            {
                *(out++) = '0';
            }
            if (value == 0)
            {
                *(out++) = '0';
            }
            else
            {
                while (value > 0)
                {
                    *(out++) = hexUppercase(value % 16);
                    value /= 16;
                }
            }
        }

        /// And reverse.
        std::reverse(begin, out);

        *(out++) = '\0';
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnUInt64 * col = typeid_cast<const ColumnUInt64 *>(column.get()))
        {
            const ColumnUInt64::Container_t & vec_in = col->getData();

            std::shared_ptr<ColumnString> col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();

            vec_res.resize(vec_in.size() * 18); /// the longest value is: xx:xx:xx:xx:xx:xx\0
            offsets_res.resize(vec_in.size());
            char * begin = reinterpret_cast<char *>(&vec_res[0]);
            char * pos = begin;

            for (size_t i = 0; i < vec_in.size(); ++i)
            {
                formatMAC(vec_in[i], pos);
                offsets_res[i] = pos - begin;
            }

            vec_res.resize(pos - begin);
        }
        else if (const ColumnConst<UInt64> * col = typeid_cast<const ColumnConst<UInt64> *>(column.get()))
        {
            char buf[18];
            char * pos = buf;
            formatMAC(col->getData(), pos);

            auto col_res = std::make_shared<ColumnConstString>(col->size(), buf);
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionMACStringToNum : public IFunction
{
public:
    static constexpr auto name = "MACStringToNum";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionMACStringToNum>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeUInt64>();
    }

    static UInt64 parseMAC(const char * pos)
    {

        /// get integer value for a hexademical char digit, or -1
        const auto number_by_char = [] (const char ch)
        {
            if ('A' <= ch && ch <= 'F')
                return 10 + ch - 'A';

            if ('a' <= ch && ch <= 'f')
                return 10 + ch - 'a';

            if ('0' <= ch && ch <= '9')
                return ch - '0';

            return -1;
        };

        UInt64 res = 0;
        for (int offset = 40; offset >= 0; offset -= 8)
        {
            UInt64 value = 0;
            size_t len = 0;
            int val = 0;
            while ((val = number_by_char(*pos)) >= 0 && len <= 2)
            {
                value = value * 16 + val;
                ++len;
                ++pos;
            }
            if (len == 0 || value > 255 || (offset > 0 && *pos != ':'))
                return 0;
            res |= value << offset;
            ++pos;
        }
        if (*(pos - 1) != '\0')
            return 0;
        return res;
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnString * col = typeid_cast<const ColumnString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnUInt64>();
            block.safeGetByPosition(result).column = col_res;

            ColumnUInt64::Container_t & vec_res = col_res->getData();
            vec_res.resize(col->size());

            const ColumnString::Chars_t & vec_src = col->getChars();
            const ColumnString::Offsets_t & offsets_src = col->getOffsets();
            size_t prev_offset = 0;

            for (size_t i = 0; i < vec_res.size(); ++i)
            {
                vec_res[i] = parseMAC(reinterpret_cast<const char *>(&vec_src[prev_offset]));
                prev_offset = offsets_src[i];
            }
        }
        else if (const ColumnConstString * col = typeid_cast<const ColumnConstString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnConst<UInt64>>(col->size(), parseMAC(col->getData().c_str()));
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
                            ErrorCodes::ILLEGAL_COLUMN);
    }
};

class FunctionMACStringToOUI : public IFunction
{
public:
    static constexpr auto name = "MACStringToOUI";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionMACStringToOUI>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeUInt64>();
    }

    static UInt64 parseMAC(const char * pos)
    {

        /// get integer value for a hexademical char digit, or -1
        const auto number_by_char = [] (const char ch)
        {
            if ('A' <= ch && ch <= 'F')
                return 10 + ch - 'A';

            if ('a' <= ch && ch <= 'f')
                return 10 + ch - 'a';

            if ('0' <= ch && ch <= '9')
                return ch - '0';

            return -1;
        };

        UInt64 res = 0;
        for (int offset = 40; offset >= 0; offset -= 8)
        {
            UInt64 value = 0;
            size_t len = 0;
            int val = 0;
            while ((val = number_by_char(*pos)) >= 0 && len <= 2)
            {
                value = value * 16 + val;
                ++len;
                ++pos;
            }
            if (len == 0 || value > 255 || (offset > 0 && *pos != ':'))
                return 0;
            res |= value << offset;
            ++pos;
        }
        if (*(pos - 1) != '\0')
            return 0;
        res = res >> 24;
        return res;
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnString * col = typeid_cast<const ColumnString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnUInt64>();
            block.safeGetByPosition(result).column = col_res;

            ColumnUInt64::Container_t & vec_res = col_res->getData();
            vec_res.resize(col->size());

            const ColumnString::Chars_t & vec_src = col->getChars();
            const ColumnString::Offsets_t & offsets_src = col->getOffsets();
            size_t prev_offset = 0;

            for (size_t i = 0; i < vec_res.size(); ++i)
            {
                vec_res[i] = parseMAC(reinterpret_cast<const char *>(&vec_src[prev_offset]));
                prev_offset = offsets_src[i];
            }
        }
        else if (const ColumnConstString * col = typeid_cast<const ColumnConstString *>(column.get()))
        {
            auto col_res = std::make_shared<ColumnConst<UInt64>>(col->size(), parseMAC(col->getData().c_str()));
            block.safeGetByPosition(result).column = col_res;
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
                            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionUUIDNumToString : public IFunction
{
private:
    static void formatHex(const UInt8 * __restrict src, UInt8 * __restrict dst, const size_t num_bytes)
    {
        /// More optimal than lookup table by nibbles.
        constexpr auto hex =
            "000102030405060708090a0b0c0d0e0f"
            "101112131415161718191a1b1c1d1e1f"
            "202122232425262728292a2b2c2d2e2f"
            "303132333435363738393a3b3c3d3e3f"
            "404142434445464748494a4b4c4d4e4f"
            "505152535455565758595a5b5c5d5e5f"
            "606162636465666768696a6b6c6d6e6f"
            "707172737475767778797a7b7c7d7e7f"
            "808182838485868788898a8b8c8d8e8f"
            "909192939495969798999a9b9c9d9e9f"
            "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf"
            "b0b1b2b3b4b5b6b7b8b9babbbcbdbebf"
            "c0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
            "d0d1d2d3d4d5d6d7d8d9dadbdcdddedf"
            "e0e1e2e3e4e5e6e7e8e9eaebecedeeef"
            "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";

        size_t src_pos = 0;
        size_t dst_pos = 0;
        for (; src_pos < num_bytes; ++src_pos)
        {
            memcpy(&dst[dst_pos], &hex[src[src_pos] * 2], 2);
            dst_pos += 2;
        }
    }

    static void formatUUID(const UInt8 * src16, UInt8 * dst36)
    {
        formatHex(&src16[0], &dst36[0], 4);
        dst36[8] = '-';
        formatHex(&src16[4], &dst36[9], 2);
        dst36[13] = '-';
        formatHex(&src16[6], &dst36[14], 2);
        dst36[18] = '-';
        formatHex(&src16[8], &dst36[19], 2);
        dst36[23] = '-';
        formatHex(&src16[10], &dst36[24], 6);
    }

public:
    static constexpr auto name = "UUIDNumToString";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionUUIDNumToString>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        const auto ptr = typeid_cast<const DataTypeFixedString *>(arguments[0].get());
        if (!ptr || ptr->getN() != uuid_bytes_length)
            throw Exception("Illegal type " + arguments[0]->getName() +
                            " of argument of function " + getName() +
                            ", expected FixedString(" + toString(uuid_bytes_length) + ")",
                            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnWithTypeAndName & col_type_name = block.safeGetByPosition(arguments[0]);
        const ColumnPtr & column = col_type_name.column;

        if (const auto col_in = typeid_cast<const ColumnFixedString *>(column.get()))
        {
            if (col_in->getN() != uuid_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(uuid_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto size = col_in->size();
            const auto & vec_in = col_in->getChars();

            auto col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            ColumnString::Offsets_t & offsets_res = col_res->getOffsets();
            vec_res.resize(size * (uuid_text_length + 1));
            offsets_res.resize(size);

            size_t src_offset = 0;
            size_t dst_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                formatUUID(&vec_in[src_offset], &vec_res[dst_offset]);
                src_offset += uuid_bytes_length;
                dst_offset += uuid_text_length;
                vec_res[dst_offset] = 0;
                ++dst_offset;
                offsets_res[i] = dst_offset;
            }
        }
        else if (const auto col_in = typeid_cast<const ColumnConst<String> *>(column.get()))
        {
            const auto data_type_fixed_string = typeid_cast<const DataTypeFixedString *>(col_in->getDataType().get());
            if (!data_type_fixed_string || data_type_fixed_string->getN() != uuid_bytes_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(uuid_bytes_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto & data_in = col_in->getData();

            char buf[uuid_text_length];
            formatUUID(reinterpret_cast<const UInt8 *>(data_in.data()), reinterpret_cast<UInt8 *>(buf));

            block.safeGetByPosition(result).column = std::make_shared<ColumnConstString>(col_in->size(), String(buf, uuid_text_length));
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionUUIDStringToNum : public IFunction
{
private:
    static void parseHex(const UInt8 * __restrict src, UInt8 * __restrict dst, const size_t num_bytes)
    {
        size_t src_pos = 0;
        size_t dst_pos = 0;
        for (; dst_pos < num_bytes; ++dst_pos)
        {
            dst[dst_pos] = unhex(src[src_pos]) * 16 + unhex(src[src_pos + 1]);
            src_pos += 2;
        }
    }

    static void parseUUID(const UInt8 * src36, UInt8 * dst16)
    {
        /// If string is not like UUID - implementation specific behaviour.

        parseHex(&src36[0], &dst16[0], 4);
        parseHex(&src36[9], &dst16[4], 2);
        parseHex(&src36[14], &dst16[6], 2);
        parseHex(&src36[19], &dst16[8], 2);
        parseHex(&src36[24], &dst16[10], 6);
    }

public:
    static constexpr auto name = "UUIDStringToNum";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionUUIDStringToNum>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        /// String or FixedString(36)
        if (!typeid_cast<const DataTypeString *>(arguments[0].get()))
        {
            const auto ptr = typeid_cast<const DataTypeFixedString *>(arguments[0].get());
            if (!ptr || ptr->getN() != uuid_text_length)
                throw Exception("Illegal type " + arguments[0]->getName() +
                                " of argument of function " + getName() +
                                ", expected FixedString(" + toString(uuid_text_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
        }

        return std::make_shared<DataTypeFixedString>(uuid_bytes_length);
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnWithTypeAndName & col_type_name = block.safeGetByPosition(arguments[0]);
        const ColumnPtr & column = col_type_name.column;

        if (const auto col_in = typeid_cast<const ColumnString *>(column.get()))
        {
            const auto & vec_in = col_in->getChars();
            const auto & offsets_in = col_in->getOffsets();
            const size_t size = offsets_in.size();

            auto col_res = std::make_shared<ColumnFixedString>(uuid_bytes_length);
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            vec_res.resize(size * uuid_bytes_length);

            size_t src_offset = 0;
            size_t dst_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                /// If string has incorrect length - then return zero UUID.
                /// If string has correct length but contains something not like UUID - implementation specific behaviour.

                size_t string_size = offsets_in[i] - src_offset;
                if (string_size == uuid_text_length + 1)
                    parseUUID(&vec_in[src_offset], &vec_res[dst_offset]);
                else
                    memset(&vec_res[dst_offset], 0, uuid_bytes_length);

                dst_offset += uuid_bytes_length;
                src_offset += string_size;
            }
        }
        else if (const auto col_in = typeid_cast<const ColumnFixedString *>(column.get()))
        {
            if (col_in->getN() != uuid_text_length)
                throw Exception("Illegal type " + col_type_name.type->getName() +
                                " of column " + col_in->getName() +
                                " argument of function " + getName() +
                                ", expected FixedString(" + toString(uuid_text_length) + ")",
                                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

            const auto size = col_in->size();
            const auto & vec_in = col_in->getChars();

            auto col_res = std::make_shared<ColumnFixedString>(uuid_bytes_length);
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & vec_res = col_res->getChars();
            vec_res.resize(size * uuid_bytes_length);

            size_t src_offset = 0;
            size_t dst_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                parseUUID(&vec_in[src_offset], &vec_res[dst_offset]);
                src_offset += uuid_text_length;
                dst_offset += uuid_bytes_length;
            }
        }
        else if (const auto col_in = typeid_cast<const ColumnConst<String> *>(column.get()))
        {
            const auto & data_in = col_in->getData();

            String res;

            if (data_in.size() == uuid_text_length)
            {
                char buf[uuid_bytes_length];
                parseUUID(reinterpret_cast<const UInt8 *>(data_in.data()), reinterpret_cast<UInt8 *>(buf));
                res.assign(buf, uuid_bytes_length);
            }
            else
                res.resize(uuid_bytes_length, '\0');

            block.safeGetByPosition(result).column = std::make_shared<ColumnConstString>(
                col_in->size(), res, std::make_shared<DataTypeFixedString>(uuid_bytes_length));
        }
        else
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
            + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionHex : public IFunction
{
public:
    static constexpr auto name = "hex";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionHex>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeFixedString *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeDate *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeDateTime *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt8 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt16 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt32 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt64 *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    template <typename T>
    void executeOneUInt(T x, char *& out)
    {
        bool was_nonzero = false;
        for (int offset = (sizeof(T) - 1) * 8; offset >= 0; offset -= 8)
        {
            UInt8 byte = static_cast<UInt8>((x >> offset) & 255);

            /// Leading zeros.
            if (byte == 0 && !was_nonzero && offset)
                continue;

            was_nonzero = true;

            *(out++) = hexUppercase(byte / 16);
            *(out++) = hexUppercase(byte % 16);
        }
        *(out++) = '\0';
    }

    template <typename T>
    bool tryExecuteUInt(const IColumn * col, ColumnPtr & col_res)
    {
        const ColumnVector<T> * col_vec = typeid_cast<const ColumnVector<T> *>(col);
        const ColumnConst<T> * col_const = typeid_cast<const ColumnConst<T> *>(col);

        static constexpr size_t MAX_UINT_HEX_LENGTH = sizeof(T) * 2 + 1;    /// Including trailing zero byte.

        if (col_vec)
        {
            auto col_str = std::make_shared<ColumnString>();
            col_res = col_str;
            ColumnString::Chars_t & out_vec = col_str->getChars();
            ColumnString::Offsets_t & out_offsets = col_str->getOffsets();

            const typename ColumnVector<T>::Container_t & in_vec = col_vec->getData();

            size_t size = in_vec.size();
            out_offsets.resize(size);
            out_vec.resize(size * 3 + MAX_UINT_HEX_LENGTH); /// 3 is length of one byte in hex plus zero byte.

            size_t pos = 0;
            for (size_t i = 0; i < size; ++i)
            {
                /// Manual exponential growth, so as not to rely on the linear amortized work time of `resize` (no one guarantees it).
                if (pos + MAX_UINT_HEX_LENGTH > out_vec.size())
                    out_vec.resize(out_vec.size() * 2 + MAX_UINT_HEX_LENGTH);

                char * begin = reinterpret_cast<char *>(&out_vec[pos]);
                char * end = begin;
                executeOneUInt<T>(in_vec[i], end);

                pos += end - begin;
                out_offsets[i] = pos;
            }

            out_vec.resize(pos);

            return true;
        }
        else if(col_const)
        {
            char buf[MAX_UINT_HEX_LENGTH];
            char * pos = buf;
            executeOneUInt<T>(col_const->getData(), pos);

            col_res = std::make_shared<ColumnConstString>(col_const->size(), buf);

            return true;
        }
        else
        {
            return false;
        }
    }

    void executeOneString(const UInt8 * pos, const UInt8 * end, char *& out)
    {
        while (pos < end)
        {
            UInt8 byte = *(pos++);
            *(out++) = hexUppercase(byte / 16);
            *(out++) = hexUppercase(byte % 16);
        }
        *(out++) = '\0';
    }

    bool tryExecuteString(const IColumn * col, ColumnPtr & col_res)
    {
        const ColumnString * col_str_in = typeid_cast<const ColumnString *>(col);
        const ColumnConstString * col_const_in = typeid_cast<const ColumnConstString *>(col);

        if (col_str_in)
        {
            auto col_str = std::make_shared<ColumnString>();
            col_res = col_str;
            ColumnString::Chars_t & out_vec = col_str->getChars();
            ColumnString::Offsets_t & out_offsets = col_str->getOffsets();

            const ColumnString::Chars_t & in_vec = col_str_in->getChars();
            const ColumnString::Offsets_t & in_offsets = col_str_in->getOffsets();

            size_t size = in_offsets.size();
            out_offsets.resize(size);
            out_vec.resize(in_vec.size() * 2 - size);

            char * begin = reinterpret_cast<char *>(&out_vec[0]);
            char * pos = begin;
            size_t prev_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                size_t new_offset = in_offsets[i];

                executeOneString(&in_vec[prev_offset], &in_vec[new_offset - 1], pos);

                out_offsets[i] = pos - begin;

                prev_offset = new_offset;
            }

            if (!out_offsets.empty() && out_offsets.back() != out_vec.size())
                throw Exception("Column size mismatch (internal logical error)", ErrorCodes::LOGICAL_ERROR);

            return true;
        }
        else if (col_const_in)
        {
            const std::string & src = col_const_in->getData();
            std::string res(src.size() * 2, '\0');
            char * pos = &res[0];
            const UInt8 * src_ptr = reinterpret_cast<const UInt8 *>(src.c_str());
            /// Let's write zero into res[res.size()]. Starting with C++ 11, this is correct.
            executeOneString(src_ptr, src_ptr + src.size(), pos);

            col_res = std::make_shared<ColumnConstString>(col_const_in->size(), res);

            return true;
        }
        else
        {
            return false;
        }
    }

    bool tryExecuteFixedString(const IColumn * col, ColumnPtr & col_res)
    {
        const ColumnFixedString * col_fstr_in = typeid_cast<const ColumnFixedString *>(col);

        if (col_fstr_in)
        {
            auto col_str = std::make_shared<ColumnString>();

            col_res = col_str;

            ColumnString::Chars_t & out_vec = col_str->getChars();
            ColumnString::Offsets_t & out_offsets = col_str->getOffsets();

            const ColumnString::Chars_t & in_vec = col_fstr_in->getChars();

            size_t size = col_fstr_in->size();

            out_offsets.resize(size);
            out_vec.resize(in_vec.size() * 2 + size);

            char * begin = reinterpret_cast<char *>(&out_vec[0]);
            char * pos = begin;

            size_t n = col_fstr_in->getN();

            size_t prev_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                size_t new_offset = prev_offset + n;

                executeOneString(&in_vec[prev_offset], &in_vec[new_offset], pos);

                out_offsets[i] = pos - begin;
                prev_offset = new_offset;
            }

            if (!out_offsets.empty() && out_offsets.back() != out_vec.size())
                throw Exception("Column size mismatch (internal logical error)", ErrorCodes::LOGICAL_ERROR);

            return true;
        }
        else
        {
            return false;
        }
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const IColumn * column = block.safeGetByPosition(arguments[0]).column.get();
        ColumnPtr & res_column = block.safeGetByPosition(result).column;

        if (tryExecuteUInt<UInt8>(column, res_column) ||
            tryExecuteUInt<UInt16>(column, res_column) ||
            tryExecuteUInt<UInt32>(column, res_column) ||
            tryExecuteUInt<UInt64>(column, res_column) ||
            tryExecuteString(column, res_column) ||
            tryExecuteFixedString(column, res_column))
            return;

        throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
                        + " of argument of function " + getName(),
                        ErrorCodes::ILLEGAL_COLUMN);
    }
};


class FunctionUnhex : public IFunction
{
public:
    static constexpr auto name = "unhex";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionUnhex>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    void unhexOne(const char * pos, const char * end, char *& out)
    {
        if ((end - pos) & 1)
        {
            *out = unhex(*pos);
            ++out;
            ++pos;
        }
        while (pos < end)
        {
            UInt8 major = unhex(*pos);
            ++pos;
            UInt8 minor = unhex(*pos);
            ++pos;

            *out = (major << 4) | minor;
            ++out;
        }
        *out = '\0';
        ++out;
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const ColumnPtr & column = block.safeGetByPosition(arguments[0]).column;

        if (const ColumnString * col = typeid_cast<const ColumnString *>(column.get()))
        {
            std::shared_ptr<ColumnString> col_res = std::make_shared<ColumnString>();
            block.safeGetByPosition(result).column = col_res;

            ColumnString::Chars_t & out_vec = col_res->getChars();
            ColumnString::Offsets_t & out_offsets = col_res->getOffsets();

            const ColumnString::Chars_t & in_vec = col->getChars();
            const ColumnString::Offsets_t & in_offsets = col->getOffsets();

            size_t size = in_offsets.size();
            out_offsets.resize(size);
            out_vec.resize(in_vec.size() / 2 + size);

            char * begin = reinterpret_cast<char *>(&out_vec[0]);
            char * pos = begin;
            size_t prev_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                size_t new_offset = in_offsets[i];

                unhexOne(reinterpret_cast<const char *>(&in_vec[prev_offset]), reinterpret_cast<const char *>(&in_vec[new_offset - 1]), pos);

                out_offsets[i] = pos - begin;

                prev_offset = new_offset;
            }

            out_vec.resize(pos - begin);
        }
        else if(const ColumnConstString * col = typeid_cast<const ColumnConstString *>(column.get()))
        {
            const std::string & src = col->getData();
            std::string res(src.size(), '\0');
            char * pos = &res[0];
            unhexOne(src.c_str(), src.c_str() + src.size(), pos);
            res = res.substr(0, pos - &res[0] - 1);

            block.safeGetByPosition(result).column = std::make_shared<ColumnConstString>(col->size(), res);
        }
        else
        {
            throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
                            + " of argument of function " + getName(),
                            ErrorCodes::ILLEGAL_COLUMN);
        }
    }
};


class FunctionBitmaskToArray : public IFunction
{
public:
    static constexpr auto name = "bitmaskToArray";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionBitmaskToArray>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }
    bool isInjective(const Block &) override { return true; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeUInt8 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt16 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt32 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeUInt64 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeInt8 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeInt16 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeInt32 *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeInt64 *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeArray>(arguments[0]);
    }

    template <typename T>
    bool tryExecute(const IColumn * column, ColumnPtr & out_column)
    {
        if (const ColumnVector<T> * col_from = typeid_cast<const ColumnVector<T> *>(column))
        {
            auto col_values = std::make_shared<ColumnVector<T>>();
            auto col_array = std::make_shared<ColumnArray>(col_values);
            out_column = col_array;

            ColumnArray::Offsets_t & res_offsets = col_array->getOffsets();
            typename ColumnVector<T>::Container_t & res_values = col_values->getData();

            const typename ColumnVector<T>::Container_t & vec_from = col_from->getData();
            size_t size = vec_from.size();
            res_offsets.resize(size);
            res_values.reserve(size * 2);

            for (size_t row = 0; row < size; ++row)
            {
                T x = vec_from[row];
                while (x)
                {
                    T y = (x & (x - 1));
                    T bit = x ^ y;
                    x = y;
                    res_values.push_back(bit);
                }
                res_offsets[row] = res_values.size();
            }

            return true;
        }
        else if (const ColumnConst<T> * col_from = typeid_cast<const ColumnConst<T> *>(column))
        {
            Array res;

            T x = col_from->getData();
            for (size_t i = 0; i < sizeof(T) * 8; ++i)
            {
                T bit = static_cast<T>(1) << i;
                if (x & bit)
                {
                    res.push_back(static_cast<UInt64>(bit));
                }
            }

            out_column = std::make_shared<ColumnConstArray>(
                col_from->size(), res, std::make_shared<DataTypeArray>(std::make_shared<DataTypeNumber<T>>()));

            return true;
        }
        else
        {
            return false;
        }
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const IColumn * in_column = block.safeGetByPosition(arguments[0]).column.get();
        ColumnPtr & out_column = block.safeGetByPosition(result).column;

        if (tryExecute<UInt8>(in_column, out_column) ||
            tryExecute<UInt16>(in_column, out_column) ||
            tryExecute<UInt32>(in_column, out_column) ||
            tryExecute<UInt64>(in_column, out_column) ||
            tryExecute<Int8>(in_column, out_column) ||
            tryExecute<Int16>(in_column, out_column) ||
            tryExecute<Int32>(in_column, out_column) ||
            tryExecute<Int64>(in_column, out_column))
            return;

        throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
                        + " of first argument of function " + getName(),
                        ErrorCodes::ILLEGAL_COLUMN);
    }
};

class FunctionToStringCutToZero : public IFunction
{
public:
    static constexpr auto name = "toStringCutToZero";
    static FunctionPtr create(const Context & context) { return std::make_shared<FunctionToStringCutToZero>(); }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override { return 1; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (!typeid_cast<const DataTypeFixedString *>(&*arguments[0]) &&
            !typeid_cast<const DataTypeString *>(&*arguments[0]))
            throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
            ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }


    bool tryExecuteString(const IColumn * col, ColumnPtr & col_res)
    {
        const ColumnString * col_str_in = typeid_cast<const ColumnString *>(col);
        const ColumnConstString * col_const_in = typeid_cast<const ColumnConstString *>(col);

        if (col_str_in)
        {
            auto col_str = std::make_shared<ColumnString>();
            col_res = col_str;
            ColumnString::Chars_t & out_vec = col_str->getChars();
            ColumnString::Offsets_t & out_offsets = col_str->getOffsets();

            const ColumnString::Chars_t & in_vec = col_str_in->getChars();
            const ColumnString::Offsets_t & in_offsets = col_str_in->getOffsets();

            size_t size = in_offsets.size();
            out_offsets.resize(size);
            out_vec.resize(in_vec.size());

            char * begin = reinterpret_cast<char *>(&out_vec[0]);
            char * pos = begin;

            ColumnString::Offset_t current_in_offset = 0;

            for (size_t i = 0; i < size; ++i)
            {
                const char * pos_in = reinterpret_cast<const char *>(&in_vec[current_in_offset]);
                size_t current_size = strlen(pos_in);
                memcpySmallAllowReadWriteOverflow15(pos, pos_in, current_size);
                pos += current_size;
                *pos = '\0';
                ++pos;
                out_offsets[i] = pos - begin;
                current_in_offset = in_offsets[i];
            }
            out_vec.resize(pos - begin);

            if (!out_offsets.empty() && out_offsets.back() != out_vec.size())
                throw Exception("Column size mismatch (internal logical error)", ErrorCodes::LOGICAL_ERROR);

            return true;
        }
        else if(col_const_in)
        {
            std::string res(col_const_in->getData().c_str());
            col_res = std::make_shared<ColumnConstString>(col_const_in->size(), res);

            return true;
        }
        else
        {
            return false;
        }
    }

    bool tryExecuteFixedString(const IColumn * col, ColumnPtr & col_res)
    {
        const ColumnFixedString * col_fstr_in = typeid_cast<const ColumnFixedString *>(col);

        if (col_fstr_in)
        {
            auto col_str = std::make_shared<ColumnString>();
            col_res = col_str;

            ColumnString::Chars_t & out_vec = col_str->getChars();
            ColumnString::Offsets_t & out_offsets = col_str->getOffsets();

            const ColumnString::Chars_t & in_vec = col_fstr_in->getChars();

            size_t size = col_fstr_in->size();

            out_offsets.resize(size);
            out_vec.resize(in_vec.size() + size);

            char * begin = reinterpret_cast<char *>(&out_vec[0]);
            char * pos = begin;
            const char * pos_in = reinterpret_cast<const char *>(&in_vec[0]);

            size_t n = col_fstr_in->getN();

            for (size_t i = 0; i < size; ++i)
            {
                size_t current_size = strnlen(pos_in, n);
                memcpySmallAllowReadWriteOverflow15(pos, pos_in, current_size);
                pos += current_size;
                *pos = '\0';
                out_offsets[i] = ++pos - begin;
                pos_in += n;
            }
            out_vec.resize(pos - begin);

            if (!out_offsets.empty() && out_offsets.back() != out_vec.size())
                throw Exception("Column size mismatch (internal logical error)", ErrorCodes::LOGICAL_ERROR);

            return true;
        }
        else
        {
            return false;
        }
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result) override
    {
        const IColumn * column = block.safeGetByPosition(arguments[0]).column.get();
        ColumnPtr & res_column = block.safeGetByPosition(result).column;

        if (tryExecuteFixedString(column, res_column) || tryExecuteString(column, res_column))
            return;

        throw Exception("Illegal column " + block.safeGetByPosition(arguments[0]).column->getName()
                        + " of argument of function " + getName(),
                        ErrorCodes::ILLEGAL_COLUMN);
    }
};

namespace
{
    template <typename T1, typename T2>
    UInt8 bitTest(const T1 val, const T2 pos) { return (val >> pos) & 1; };
}

class FunctionBitTest : public IFunction
{
public:
    static constexpr auto name = "bitTest";
    static FunctionPtr create(const Context &) { return std::make_shared<FunctionBitTest>(); }

    String getName() const override { return name; }

    size_t getNumberOfArguments() const override { return 2; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        const auto first_arg = arguments.front().get();
        if (!typeid_cast<const DataTypeUInt8 *>(first_arg) &&
            !typeid_cast<const DataTypeUInt16 *>(first_arg) &&
            !typeid_cast<const DataTypeUInt32 *>(first_arg) &&
            !typeid_cast<const DataTypeUInt64 *>(first_arg) &&
            !typeid_cast<const DataTypeInt8 *>(first_arg) &&
            !typeid_cast<const DataTypeInt16 *>(first_arg) &&
            !typeid_cast<const DataTypeInt32 *>(first_arg) &&
            !typeid_cast<const DataTypeInt64 *>(first_arg))
            throw Exception{
                "Illegal type " + first_arg->getName() + " of first argument of function " + getName(),
                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};

        const auto second_arg = arguments.back().get();
        if (!typeid_cast<const DataTypeUInt8 *>(second_arg) &&
            !typeid_cast<const DataTypeUInt16 *>(second_arg) &&
            !typeid_cast<const DataTypeUInt32 *>(second_arg) &&
            !typeid_cast<const DataTypeUInt64 *>(second_arg))
            throw Exception{
                "Illegal type " + second_arg->getName() + " of second argument of function " + getName(),
                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};

        return std::make_shared<DataTypeUInt8>();
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, const size_t result) override
    {
        const auto value_col = block.safeGetByPosition(arguments.front()).column.get();

        if (!execute<UInt8>(block, arguments, result, value_col) &&
            !execute<UInt16>(block, arguments, result, value_col) &&
            !execute<UInt32>(block, arguments, result, value_col) &&
            !execute<UInt64>(block, arguments, result, value_col) &&
            !execute<Int8>(block, arguments, result, value_col) &&
            !execute<Int16>(block, arguments, result, value_col) &&
            !execute<Int32>(block, arguments, result, value_col) &&
            !execute<Int64>(block, arguments, result, value_col))
            throw Exception{
                "Illegal column " + value_col->getName() + " of argument of function " + getName(),
                ErrorCodes::ILLEGAL_COLUMN};
    }

private:
    template <typename T> bool execute(
        Block & block, const ColumnNumbers & arguments, const size_t result,
        const IColumn * const value_col_untyped)
    {
        if (const auto value_col = typeid_cast<const ColumnVector<T> *>(value_col_untyped))
        {
            const auto pos_col = block.safeGetByPosition(arguments.back()).column.get();

            if (!execute(block, arguments, result, value_col, pos_col))
                throw Exception{
                    "Illegal column " + pos_col->getName() + " of argument of function " + getName(),
                    ErrorCodes::ILLEGAL_COLUMN};

            return true;
        }
        else if (const auto value_col = typeid_cast<const ColumnConst<T> *>(value_col_untyped))
        {
            const auto pos_col = block.safeGetByPosition(arguments.back()).column.get();

            if (!execute(block, arguments, result, value_col, pos_col))
                throw Exception{
                    "Illegal column " + pos_col->getName() + " of argument of function " + getName(),
                    ErrorCodes::ILLEGAL_COLUMN};

            return true;
        }

        return false;
    }

    template <typename ValueColumn> bool execute(
        Block & block, const ColumnNumbers & arguments, const size_t result,
        const ValueColumn * const value_col, const IColumn * const pos_col)
    {
        return execute<UInt8>(block, arguments, result, value_col, pos_col) ||
               execute<UInt16>(block, arguments, result, value_col, pos_col) ||
               execute<UInt32>(block, arguments, result, value_col, pos_col) ||
               execute<UInt64>(block, arguments, result, value_col, pos_col);
    }

    template <typename T, typename ValueType> bool execute(
        Block & block, const ColumnNumbers & arguments, const size_t result,
        const ColumnVector<ValueType> * const value_col, const IColumn * const pos_col_untyped)
    {
        if (const auto pos_col = typeid_cast<const ColumnVector<T> *>(pos_col_untyped))
        {
            const auto & values = value_col->getData();
            const auto & positions = pos_col->getData();

            const auto size = value_col->size();
            const auto out_col = std::make_shared<ColumnUInt8>(size);
            ColumnPtr out_col_ptr{out_col};
            block.safeGetByPosition(result).column = out_col_ptr;

            auto & out = out_col->getData();

            for (const auto i : ext::range(0, size))
                out[i] = bitTest(values[i], positions[i]);

            return true;
        }
        else if (const auto pos_col = typeid_cast<const ColumnConst<T> *>(pos_col_untyped))
        {
            const auto & values = value_col->getData();

            const auto size = value_col->size();
            const auto out_col = std::make_shared<ColumnUInt8>(size);
            ColumnPtr out_col_ptr{out_col};
            block.safeGetByPosition(result).column = out_col_ptr;

            auto & out = out_col->getData();

            for (const auto i : ext::range(0, size))
                out[i] = bitTest(values[i], pos_col->getData());

            return true;
        }

        return false;
    }

    template <typename T, typename ValueType> bool execute(
        Block & block, const ColumnNumbers & arguments, const size_t result,
        const ColumnConst<ValueType> * const value_col, const IColumn * const pos_col_untyped)
    {
        if (const auto pos_col = typeid_cast<const ColumnVector<T> *>(pos_col_untyped))
        {
            const auto & positions = pos_col->getData();

            const auto size = value_col->size();
            const auto out_col = std::make_shared<ColumnUInt8>(size);
            ColumnPtr out_col_ptr{out_col};
            block.safeGetByPosition(result).column = out_col_ptr;

            auto & out = out_col->getData();

            for (const auto i : ext::range(0, size))
                out[i] = bitTest(value_col->getData(), positions[i]);

            return true;
        }
        else if (const auto pos_col = typeid_cast<const ColumnConst<T> *>(pos_col_untyped))
        {
            block.safeGetByPosition(result).column = std::make_shared<ColumnConst<UInt8>>(
                value_col->size(),
                bitTest(value_col->getData(), pos_col->getData()));

            return true;
        }

        return false;
    }
};

template <typename Impl>
struct FunctionBitTestMany : public IFunction
{
public:
    static constexpr auto name = Impl::name;
    static FunctionPtr create(const Context &) { return std::make_shared<FunctionBitTestMany>(); }

    String getName() const override { return name; }

    bool isVariadic() const override { return true; }
    size_t getNumberOfArguments() const override { return 0; }

    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
    {
        if (arguments.size() < 2)
            throw Exception{
                "Number of arguments for function " + getName() + " doesn't match: passed "
                + toString(arguments.size()) + ", should be at least 2.",
                ErrorCodes::TOO_LESS_ARGUMENTS_FOR_FUNCTION};

        const auto first_arg = arguments.front().get();
        if (!typeid_cast<const DataTypeUInt8 *>(first_arg) && !typeid_cast<const DataTypeUInt16 *>(first_arg) &&
            !typeid_cast<const DataTypeUInt32 *>(first_arg) && !typeid_cast<const DataTypeUInt64 *>(first_arg) &&
            !typeid_cast<const DataTypeInt8 *>(first_arg) && !typeid_cast<const DataTypeInt16 *>(first_arg) &&
            !typeid_cast<const DataTypeInt32 *>(first_arg) && !typeid_cast<const DataTypeInt64 *>(first_arg))
            throw Exception{
                "Illegal type " + first_arg->getName() + " of first argument of function " + getName(),
                ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};


        for (const auto i : ext::range(1, arguments.size()))
        {
            const auto pos_arg = arguments[i].get();

            if (!typeid_cast<const DataTypeUInt8 *>(pos_arg) && !typeid_cast<const DataTypeUInt16 *>(pos_arg) &&
                !typeid_cast<const DataTypeUInt32 *>(pos_arg) && !typeid_cast<const DataTypeUInt64 *>(pos_arg))
                throw Exception{
                    "Illegal type " + pos_arg->getName() + " of " + toString(i) + " argument of function " + getName(),
                    ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
        }

        return std::make_shared<DataTypeUInt8>();
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, const size_t result) override
    {
        const auto value_col = block.safeGetByPosition(arguments.front()).column.get();

        if (!execute<UInt8>(block, arguments, result, value_col) &&
            !execute<UInt16>(block, arguments, result, value_col) &&
            !execute<UInt32>(block, arguments, result, value_col) &&
            !execute<UInt64>(block, arguments, result, value_col) &&
            !execute<Int8>(block, arguments, result, value_col) &&
            !execute<Int16>(block, arguments, result, value_col) &&
            !execute<Int32>(block, arguments, result, value_col) &&
            !execute<Int64>(block, arguments, result, value_col))
            throw Exception{
                "Illegal column " + value_col->getName() + " of argument of function " + getName(),
                ErrorCodes::ILLEGAL_COLUMN};
    }

private:
    template <typename T> bool execute(
        Block & block, const ColumnNumbers & arguments, const size_t result,
        const IColumn * const value_col_untyped)
    {
        if (const auto value_col = typeid_cast<const ColumnVector<T> *>(value_col_untyped))
        {
            const auto size = value_col->size();
            bool is_const;
            const auto mask = createConstMask<T>(size, block, arguments, is_const);
            const auto & val = value_col->getData();

            const auto out_col = std::make_shared<ColumnUInt8>(size);
            ColumnPtr out_col_ptr{out_col};
            block.safeGetByPosition(result).column = out_col_ptr;

            auto & out = out_col->getData();

            if (is_const)
            {
                for (const auto i : ext::range(0, size))
                    out[i] = Impl::combine(val[i], mask);
            }
            else
            {
                const auto mask = createMask<T>(size, block, arguments);

                for (const auto i : ext::range(0, size))
                    out[i] = Impl::combine(val[i], mask[i]);
            }

            return true;
        }
        else if (const auto value_col = typeid_cast<const ColumnConst<T> *>(value_col_untyped))
        {
            const auto size = value_col->size();
            bool is_const;
            const auto mask = createConstMask<T>(size, block, arguments, is_const);
            const auto val = value_col->getData();

            if (is_const)
            {
                block.safeGetByPosition(result).column = std::make_shared<ColumnConst<UInt8>>(
                    size, Impl::combine(val, mask));
            }
            else
            {
                const auto mask = createMask<T>(size, block, arguments);
                const auto out_col = std::make_shared<ColumnUInt8>(size);
                ColumnPtr out_col_ptr{out_col};
                block.safeGetByPosition(result).column = out_col_ptr;

                auto & out = out_col->getData();

                for (const auto i : ext::range(0, size))
                    out[i] = Impl::combine(val, mask[i]);
            }

            return true;
        }

        return false;
    }

    template <typename ValueType>
    ValueType createConstMask(const std::size_t size, const Block & block, const ColumnNumbers & arguments, bool & is_const)
    {
        is_const = true;
        ValueType mask{};

        for (const auto i : ext::range(1, arguments.size()))
        {
            const auto pos_col = block.safeGetByPosition(arguments[i]).column.get();

            if (pos_col->isConst())
            {
                const auto pos = static_cast<const ColumnConst<ValueType> *>(pos_col)->getData();
                mask = mask | 1 << pos;
            }
            else
            {
                is_const = false;
                return {};
            }
        }

        return mask;
    }

    template <typename ValueType>
    PaddedPODArray<ValueType> createMask(const std::size_t size, const Block & block, const ColumnNumbers & arguments)
    {
        PaddedPODArray<ValueType> mask(size, ValueType{});

        for (const auto i : ext::range(1, arguments.size()))
        {
            const auto pos_col = block.safeGetByPosition(arguments[i]).column.get();

            if (!addToMaskImpl<UInt8>(mask, pos_col) && !addToMaskImpl<UInt16>(mask, pos_col) &&
                !addToMaskImpl<UInt32>(mask, pos_col) && !addToMaskImpl<UInt64>(mask, pos_col))
                throw Exception{
                    "Illegal column " + pos_col->getName() + " of argument of function " + getName(),
                    ErrorCodes::ILLEGAL_COLUMN};
        }

        return mask;
    }

    template <typename PosType, typename ValueType>
    bool addToMaskImpl(PaddedPODArray<ValueType> & mask, const IColumn * const pos_col_untyped)
    {
        if (const auto pos_col = typeid_cast<const ColumnVector<PosType> *>(pos_col_untyped))
        {
            const auto & pos = pos_col->getData();

            for (const auto i : ext::range(0, mask.size()))
                mask[i] = mask[i] | (1 << pos[i]);

            return true;
        }
        else if (const auto pos_col = typeid_cast<const ColumnConst<PosType> *>(pos_col_untyped))
        {
            const auto & pos = pos_col->getData();
            const auto new_mask = 1 << pos;

            for (const auto i : ext::range(0, mask.size()))
                mask[i] = mask[i] | new_mask;

            return true;
        }

        return false;
    }
};

struct BitTestAnyImpl
{
    static constexpr auto name = "bitTestAny";
    template <typename T> static UInt8 combine(const T val, const T mask) { return (val & mask) != 0; }
};

struct BitTestAllImpl
{
    static constexpr auto name = "bitTestAll";
    template <typename T> static UInt8 combine(const T val, const T mask) { return (val & mask) == mask; }
};

using FunctionBitTestAny = FunctionBitTestMany<BitTestAnyImpl>;
using FunctionBitTestAll = FunctionBitTestMany<BitTestAllImpl>;


}