Question

My team and I have this nasty problem with parsing a string received from our server. The server is pretty simple socket stuff done in qt here is the sendData function:

void sendData(QTcpSocket *client,QString response){
QString text = response.toUtf8();
QByteArray block;
QDataStream out(&block, QIODevice::WriteOnly);
out << (quint32)0;
out << text;
out.device()->seek(0);
out << (quint32)(block.size() - sizeof(quint32));
try{
    client->write(block);
}
catch(...){...

The client is in Java and is also pretty standard socket stuff, here is where we are at now after trying many many different ways of decoding the response from the server:

Socket s;
try {
    s = new Socket(URL, 1987);

    PrintWriter output = new PrintWriter(s.getOutputStream(), true);
    InputStreamReader inp = new InputStreamReader(s.getInputStream(), Charset.forName("UTF-8"));
    BufferedReader rd = new BufferedReader( inp );

    String st;
    while ((st = rd.readLine()) != null){
        System.out.println(st);
    }...

If a connection is made with the server it sends a string “Send Handshake” with the size of the string in bytes sent before it as seen in the first block of code. This notifies the client that it should send authentication to the server. As of now the string we get from the server looks like this:
������ ��������S��e��n��d�� ��H��a��n��d��s��h��a��k��e

We have used tools such as string encode/decode tool to try and assess how the string is encoded but it fails on every configuration.

We are out of ideas as to what encoding this is, if any, or how to fix it.
Any help would be much appreciated.

Answer 1

At a glance, the line where you convert the QString parameter to a Utf8 QByteArray and then back to a QString seems odd:

QString text = response.toUtf8();

When the QByteArray returned by toUtf8() is assigned to text, I think it is assumed that the QByteArray contains an Ascii (char*) buffer.