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mke_encode_chunking

//-----------------------
// Set encoded file name
//-----------------------
string encodedFileName = "encodedText";

//-----------------------------------
// Create default MTE MKE and Status
//-----------------------------------
MteMkeEnc mkeEncoder = new MteMkeEnc();
MteStatus encoderStatus;

//------------------------------------------------------------------------
// Set identifier
// These values should be treated like encryption keys
// The following personalization string and nonce values are for
// demonstration only and should not be used in a production environment
//------------------------------------------------------------------------
string identifier = "demo";

string fPath = string.Empty;
//--------------------------------------------------
// Prompt for path till we have one and it is valid
//--------------------------------------------------
while (string.IsNullOrWhiteSpace(fPath) || !File.Exists(fPath))
{
    //------------------------------------
    // Prompting message for file to copy
    //------------------------------------
    Console.WriteLine("Please enter path to file\n");

    fPath = Console.ReadLine();
    //-------------------------------
    // Check to make sure file exits
    //-------------------------------
    if (!File.Exists(fPath))
    {
        Console.WriteLine($"File at the path '{fPath}' does not exist");
    }
}
//----------------------------------------
// Set the correct extension for the file
//----------------------------------------
encodedFileName = $"{encodedFileName}{Path.GetExtension(fPath)}";

//---------------------------------------------------------------------
// Check how long entropy we need, set default all 0's
// should be treated like encryption keys - this is just example
//---------------------------------------------------------------------
int entropyMinBytes = mkeEncoder.GetDrbgsEntropyMinBytes(mkeEncoder.GetDrbg());
string entropy = (entropyMinBytes > 0) ? new String('0', entropyMinBytes) : entropy;

//--------------------------------
// Set MKE values for the Encoder
//--------------------------------
mkeEncoder.SetEntropy(Encoding.UTF8.GetBytes(entropy));
mkeEncoder.SetNonce(0);

//-------------------------
// Initialize MKE Encoder
//-------------------------
encoderStatus = mkeEncoder.Instantiate(identifier);
if (encoderStatus != MteStatus.mte_status_success)
{
    throw new ApplicationException($"Failed to initialize the MTE encoder engine. Status: " +
    $"{mkeEncoder.GetStatusName(encoderStatus)} / {mkeEncoder.GetStatusDescription(encoderStatus)}");
}
//-----------------------------
// Initialize chunking session
//-----------------------------
encoderStatus = mkeEncoder.StartEncrypt();
if(encoderStatus != MteStatus.mte_status_success)
{
    throw new Exception("Failed to start encode chunk. Status: "
        + mkeEncoder.GetStatusName(encoderStatus)+ " / "
        + mkeEncoder.GetStatusDescription(encoderStatus));
}
//-------------------------------------------------------
// Before we start we want to delete any files
// that are already there in order to create new ones
//-------------------------------------------------------
if (File.Exists(encodedFileName))
{
    File.Delete(encodedFileName);
}
//------------------------------------
// Read file in and encode using MKE
//------------------------------------
using (FileStream stream = File.OpenRead(fPath))
    using (FileStream writeStream = File.OpenWrite(encodedFileName))
    {
        BinaryReader reader = new BinaryReader(stream);
        BinaryWriter writer = new BinaryWriter(writeStream);

        //-----------------------------------
        // Create a buffer to hold the bytes
        //-----------------------------------
        byte[] buffer = new Byte[1024];
        int bytesRead;
        //------------------------------------------
        // While the read method returns bytes
        // Keep writing them to the output stream
        //------------------------------------------
        while ((bytesRead = stream.Read(buffer, 0, 1024)) > 0)
        {
            //-------------------------------
            // Encode the data in place
            // encoded data put back in buffer
            //-------------------------------
            MteStatus chunkStatus = mkeEncoder.EncryptChunk(buffer, 0, bytesRead);
            if(chunkStatus != MteStatus.mte_status_success)
            {
                throw new Exception("Failed to encode chunk. Status: "
                    + mkeEncoder.GetStatusName(chunkStatus)+ " / "
                    + mkeEncoder.GetStatusDescription(chunkStatus));
            }
            writeStream.Write(buffer, 0, bytesRead);
        }
        //-----------------------------
        // Finish the chunking session
        //-----------------------------
        byte[] finalEncodedChunk = mkeEncoder.FinishEncrypt(out MteStatus finishStatus);
        if(finishStatus != MteStatus.mte_status_success)
        {
            throw new Exception("Failed to finish encode chunk. Status: "
                + mkeEncoder.GetStatusName(finishStatus)+ " / "
                + mkeEncoder.GetStatusDescription(finishStatus));
        }
        //-----------------------------------
        // Append the final data to the file
        //-----------------------------------
        writeStream.Write(finalEncodedChunk, 0, finalEncodedChunk.Length);
    }