Шифрование XOR файла в WinForms C++

void gamma(FileStream^ in, FileStream^ out, Byte gamma_val)
{
    array<Byte> ^buf = nullptr;
 
    BinaryReader ^ br = gcnew BinaryReader(in);
    buf = br->ReadBytes(in->Length);
    br->Close();
 
    BinaryWriter ^ bw = gcnew BinaryWriter(out);
    for (int i = 0; i < buf->Length; i++)
    {
            bw->Write(buf[i] ^ gamma_val);
    }
 
    in->Close();
    out->Close();
    delete in;
    delete out;
    bw->Close();
    br->Close();
        
}

int gamma_val = some_int_value;
gamma(gcnew FileStream(in_name, FileMode::Open), gcnew FileStream(out_name, FileMode::OpenOrCreate), (Byte)gamma_val);

for (int i = 0; i < buf->Length; i++)
    {
            bw->Write(Byte(buf[i] ^ gamma_val));
    }

void gamma(FileStream^ in, FileStream^ out, Byte gamma_val)
{
    array<Byte> ^buf = nullptr;
 
    BinaryReader ^ br = gcnew BinaryReader(in);
    buf = br->ReadBytes(in->Length);
    br->Close();
 
    BinaryWriter ^ bw = gcnew BinaryWriter(out);
    for (int i = 0; i < buf->Length; i++)
    {
            bw->Write(Byte(buf[i] ^ gamma_val));
    }
 
    in->Close();
    out->Close();
    bw->Close();
    br->Close();
        
}