Question

Assume that there’s no problem with my header file and some included library. I’m using Winsock2.

//main.cpp and this code is okie, I omit some codes for readable reason
SOCKET ClientSocket;
ClientSocket = INVALID_SOCKET;
ClientSocket = accept(ListenSocket, NULL, NULL);
cout <<"a client is connected" << endl;
ClientConnection connection(ClientSocket);
connection.run();

//ClientConnection.h I tested any function and it's okie
class ClientConnection{
    private:
        SOCKET connectedSocket;
        bool connected;
    public:
        ClientConnection(const ClientConnection &con);
        ClientConnection(SOCKET s);
        int processMessage(string message);
        void sendMessage(string message);
        string recvMessage();
        int run();
        void printSomething(); //function just print something such as :"Here"
};

In run() function, I call the recvMessage() to get the message from client then I call processMessage(message). This is my processMessage(message) and sendMessage:

void ClientConnection::sendMessage(string mess){
    const char* sendBuff = mess.c_str();    
    int error = send(this->connectedSocket,sendBuff, (int)strlen(sendBuff), 0);
    delete sendBuff;
    return ;
}
int ClientConnection::processMessage(string message){
    cout << "This is message from client:\n" << message << endl;
    ImageProcessingPlugin *plugin = new ImageProcessingPlugin();
    plugin-> processMessage( *this, message);
    delete plugin;
    return 0;
}

This is ImageProcessingPlugin:

// ImageProcessingPlugin.h
class ImageProcessingPlugin : public Plugin{
public:
    ImageProcessingPlugin();
    void processMessage(const ClientConnection &connection, string message);
};
// ImageProcessingPlugin.cpp
void ImageProcessingPlugin::processMessage(const ClientConnection& _connection,  string message){
    ClientConnection connection(_connection);
    connection.printSomething() // It's okie
    connection.sendMessage("Server received"); // Problem goes here!!
    return;
}

After debugging, when I call printSomething() in plugin->processMessage, it’s still ok, but when I go to sendMessage, the client still got the message “Server received” from server, but there was an error: “_Block_Type_IS_VALID(pHead->nBlockUse)”! Anyone can solve my problem?

Answer 1

Your deleting delete sendBuff; here, but you never allocated the memory yourself. Try removing that line.