Memory leakage in QLocalServer/QLocalSocket

Question

I have some problem in using QLocalServer/QLocalSocket.

I'm sending raw pixel data from server to client, and there is a huge memory leakage while process. but I couldn't know what is the reason...

Memory increases about 20MB/1sec (when I checked with my eyes in system administrator.)

Followings are my codes.

Server

void qsharedServer::updateImageData(unsigned char* r_data, int r_width, int r_height, int r_step, int r_label_i){

QLocalSocket* connection = 0;
connection = clientSocket;

if (connection)
{
    if (connection->isOpen())
    {
        QByteArray block;
        QDataStream out(&block, QIODevice::WriteOnly);

        out.setVersion(QDataStream::Qt_5_7);
        const char* rc_data = reinterpret_cast<const char*>(r_data);

        out <<r_step*r_height<< r_width << r_height << r_step;
        out.writeBytes(rc_data, r_step*r_height);
        connection->write(block);
        connection->flush();
    }
}

Client

void qsharedClient::readSocket(){

    QByteArray block = connection->readAll();
    QDataStream in(&block, QIODevice::ReadOnly);
    in.setVersion(QDataStream::Qt_5_7);

    /* Read Raw Data */
    char* data;
    uint size;
    int width;
    int height;
    int step;
    while (!in.atEnd())
    {
        in >> size >> width >> height >> step;
        in.readBytes(data, size);
    }
    emit drawData((unsigned char*)data, width, height, step);
}

These two codes can communicate well, but memories are increasing very sharply and terminated when it over certain level.

I tried like connection->reset() or QByteArray::clear()..etc but it doesn't worked.

Is there any idea with my problem??

How about using QTcpServer/QTcpSocket?? This can solve my problem??

Please share your idea. Thanks!!

Answer 1

This should be happening because named pipe stores all data until you close it. As a solution you should call disconnectFromServer() for socket (on the sender or receiver side - does not matter) once you have sent/received enough data for one packet.