QSerial without QThreads - qt

Question

I create a "server" lib with a Qt GUI.
I don't and can't use QThreads because this is supposed to be as independent from Qt as possible, and because I have other threads already working like a Ethernet part.
The thread ExternalRs232Thread() is lauched by the public function RunExternalRs232()
RunExternalRs232() opens the serial port, returns -1 if can't open serial, and if is ok runs the function ExternalRs232Thread() in a detached thread.
Initially, I have tried to run this with Serialib, but this never works properly with the Qt project. So I decided to give QSerialPort a try like this:
Server.h
#ifndef SERVER_H
#define SERVER_H
#include <iostream>
#include <winsock2.h>
#include <windows.h>
#include <thread>
#include <unordered_map>
#include <unordered_set>
#include <sstream>
#include <time.h>
#include <chrono>
#include <mutex>
#include <QObject>
#include "libs/json.hpp"
#include <QtSerialPort>
#include "hdlccsvparser.h"
using namespace std;
using json = nlohmann::json;
using std::chrono::milliseconds;
using std::chrono::duration_cast;
using std::chrono::seconds;
using std::chrono::system_clock;
struct Contact {
int port; //udp port of te contact
time_t time; //last communication date ( is still active ? )
};
class Server : public QObject
{
Q_OBJECT
public:
Server();
virtual ~Server();
[...]
//return 0 if sucess , 1 port is not usabe, 2 port already in use
int RunExternalRs232(string PortCom, unsigned int baudrate);
int StopExternalRs232(string PortCom);
[...]
//clean exit
void ExitServer();
signals:
[...]
private:
[...]
// External ThreadS and exiting loop of threadS in set (if key d'ont exist anymore, exit loop)
mutex mtxExternalRs232;
unordered_set<string> ExternalRs232PortActiveList;
void ExternalRs232Thread(QSerialPort* Rs232Connection, string port);
[...]
};
#endif // SERVER_H
Server.cpp
#include "Server/Server.h"
#include <winsock2.h>
/* Public Part*/
[...]
int Server::RunExternalRs232(string PortCom, unsigned int baudrate){
//PortCom = (char *)"COM1";
//baudrate = 9600;
QSerialPort Rs232Connection;
// Connection to serial port
// COMxx
Rs232Connection.setPortName(QString::fromStdString(PortCom));
Rs232Connection.setBaudRate(baudrate);
Rs232Connection.setDataBits(QSerialPort::Data8);
Rs232Connection.setParity(QSerialPort::NoParity);
Rs232Connection.setStopBits(QSerialPort::OneStop);
Rs232Connection.setFlowControl(QSerialPort::NoFlowControl);
int i = Rs232Connection.open(QIODevice::ReadWrite);
// If connection fails, errorOpening != 1
if(i != 1){
return i;
}
mtxExternalRs232.lock();
ExternalRs232PortActiveList.insert(PortCom);
mtxExternalRs232.unlock();
cout << "External Rs232 starting on " << PortCom << endl;
stringstream sstmp;
sstmp << PortCom;
emit LogMessage(QString::fromStdString("External Rs232 starting on " + sstmp.str()),0);
std::thread thServer(&Server::ExternalRs232Thread,this,&Rs232Connection,PortCom);
thServer.detach();
return 0;
}
int Server::StopExternalRs232(string PortCom){
PortCom = "COM1";
mtxExternalRs232.lock();
/*
if(ExternalRs232PortActiveList.count(PortCom) != 1){ //???
//port not in use
cerr << "close Failed Rs232 " << PortCom << endl;
mtxExternalRs232.unlock();
return 1;
}*/
cout << "close External Rs232 " << PortCom << endl;
ExternalRs232PortActiveList.erase(PortCom);
mtxExternalRs232.unlock();
return 0;
mtxExternalRs232.lock();
cout << ExternalRs232PortActiveList.count(PortCom) << " here " << endl;
mtxExternalRs232.unlock();
}
[...]
/* Private Part */
/* Thread part */
[...]
void Server::ExternalRs232Thread(QSerialPort * Rs232Connection, string port){
//char/binary read on rs232
char tmp;
//if rs232 has data
bool res = false;
stringstream message;
Rs232Connection->write("H");
mtxExternalRs232.lock();
int iscount = ExternalRs232PortActiveList.count(port);
mtxExternalRs232.unlock();
while(iscount == 1){
res = false;
if(!Rs232Connection->waitForReadyRead(300)){
//no data skipp
} else {
QByteArray datas = Rs232Connection->readAll();
QTextCodec *codec = QTextCodec::codecForName("UTF-8");
string tmp = codec->toUnicode(datas).toStdString();
cout << tmp << endl;
}
mtxExternalRs232.lock();
iscount = ExternalRs232PortActiveList.count(port);
mtxExternalRs232.unlock();
}
Rs232Connection->flush();
Rs232Connection->close();
}
[...]
/* functions part */
[...]
Server::Server(){
//init winsock
if(WSAStartup(MAKEWORD(2,2),&wsa) != 0){
cerr << "Could not init winsock2 : " << WSAGetLastError();
}
//creating a socket
if((s = socket(AF_INET, SOCK_DGRAM, 0)) == INVALID_SOCKET){
cerr << "Could not create a socket : " << WSAGetLastError();
}
}
Server::~Server(){
//dtor
}
at the end, I get
QObject::startTimer: Timers can only be used with threads started with QThreads
So how is possible to run Serial Rs232 without using QThreads?