I need help implementing signed VarInt's in C++

Question

I have been working on a program that can connect to a Minecraft Server and exchange packets with it but Minecraft's server packets heavily rely on signed VarInts. On the site documenting how their communication works is explanation of VarInt and even an example implementation of them in Java:

So i followed it and it works for non negative numbers but for negative numbers it's just goes infinitely long. I serched for other means of implementing it but i couldn't find any.

Here is my version it (works as i said only for positive numbers which is not fully what i want)

class VarInt
{
public:
    char* data = NULL;
    int length = 0;

    int Read();
    void Write(int value);

    ~VarInt();
private:
    int SEGMENT_BIT_MASK = 0x7F;
    int CONTINUE_BIT_MASK = 0x80;

};

int VarInt::Read()
{
    int value = 0;
    int position = 0;
    byte currentByte;

    int i = 0;
    while (true)
    {
        currentByte = data[i];
        value |= (currentByte & SEGMENT_BIT_MASK) << position;

        if ((currentByte & CONTINUE_BIT_MASK) == 0)
            break;

        i++;
        position += 7;

        if (position >= 32)
            std::cout << "VarInt is too Big" << std::endl;
    }
    return value;
};

void VarInt::Write(int value)
{
    bool state = true;
    std::vector<byte> bytes;

    while (state)
    {
        if ((value & ~SEGMENT_BIT_MASK) == 0)
        {
            bytes.push_back(value);
            state = false;
            break;
        }
        bytes.push_back(((value & SEGMENT_BIT_MASK) | CONTINUE_BIT_MASK));
        value >>= 7;
    }

    int bytes_size = bytes.size();

    length = bytes_size;
    data = (char*)malloc(bytes_size);

    int i = 0;
    while (i != bytes_size)
    {
        data[i] = bytes.at(i);
        i++;
    }
};

VarInt::~VarInt()
{

};

And here are my means of testing it:

#include <iostream>
#include "MDatatypes.h"

int main()
{
    ndt::VarInt test;
    //Sets value of test to -127
    test.Write(-127);

    //Sets value of test2 to 255
    ndt::VarInt test2;
    test2.Write(255);

    //Outputing length of each Varint in bytes
    std::cout << test.length << '|' << test2.length << std::endl;
    //Outputing the values of each Varint
    std::cout << test.Read() << '|' << test2.Read() << std::endl;
}