C++ Serial port with USB hub - c++

Question

I want to connect a seairl port with C++ using USB hub (USB splliter).
I have a code that works perfectly fine with my COM ports, but when I'm trying to use the USB hub, I get an error says the COM port not available (even though I see it in the device manager).
I there a way to connect a USB hub COM port in C++?
I attached my current code if necessary. Thank you!
SerialPort.hpp:
/*
* Author: Manash Kumar Mandal
* Modified Library introduced in Arduino Playground which does not work
* This works perfectly
* LICENSE: MIT
*/
#pragma once
#define ARDUINO_WAIT_TIME 2000
#define MAX_DATA_LENGTH 1024
#include <windows.h>
#include <iostream>
#include <string>
class SerialPort {
private:
std::string readBuffer;
HANDLE handler;
bool connected;
COMSTAT status;
DWORD errors;
public:
explicit SerialPort(const char* portName, DWORD baudRate = CBR_9600);
~SerialPort();
int readSerialPort(const char* buffer, unsigned int buf_size);
int readSerialPortUntil(std::string* payload, std::string until);
bool writeSerialPort(const char* buffer, unsigned int buf_size);
bool writeSerialPort(std::string payload);
bool isConnected();
void closeSerial();
};
SerialPort.cpp:
/*
* Author: Manash Kumar Mandal
* Modified Library introduced in Arduino Playground which does not work
* This works perfectly
* LICENSE: MIT
*/
#include <windows.h>
#include <iostream>
#include <string>
#include "SerialPort.hpp"
SerialPort::SerialPort(const char* portName, DWORD baudRate) {
this->connected = false;
this->handler = CreateFileA(static_cast<LPCSTR>(portName),
GENERIC_READ | GENERIC_WRITE,
0,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (this->handler == INVALID_HANDLE_VALUE) {
if (GetLastError() == ERROR_FILE_NOT_FOUND) {
std::cerr << "ERROR: Handle was not attached.Reason : " << portName << " not available\n";
} else {
std::cerr << "ERROR!!!\n";
}
} else {
DCB dcbSerialParameters = { 0 };
if (!GetCommState(this->handler, &dcbSerialParameters)) {
std::cerr << "ERROR: Failed to get current serial parameters\n";
} else {
dcbSerialParameters.BaudRate = baudRate;
dcbSerialParameters.ByteSize = 8;
dcbSerialParameters.StopBits = ONESTOPBIT;
dcbSerialParameters.Parity = NOPARITY;
dcbSerialParameters.fDtrControl = DTR_CONTROL_ENABLE;
if (!SetCommState(handler, &dcbSerialParameters)) {
std::cout << "ALERT: could not set serial port parameters\n";
} else {
this->connected = true;
PurgeComm(this->handler, PURGE_RXCLEAR | PURGE_TXCLEAR);
Sleep(ARDUINO_WAIT_TIME);
}
}
}
}
SerialPort::~SerialPort() {
if (this->connected) {
this->connected = false;
CloseHandle(this->handler);
}
}
// Reading bytes from serial port to buffer;
// returns read bytes count, or if error occurs, returns 0
int SerialPort::readSerialPort(const char* buffer, unsigned int buf_size) {
DWORD bytesRead{};
unsigned int toRead = 0;
ClearCommError(this->handler, &this->errors, &this->status);
if (this->status.cbInQue > 0) {
if (this->status.cbInQue > buf_size) {
toRead = buf_size;
} else {
toRead = this->status.cbInQue;
}
}
memset((void*)buffer, 0, buf_size);
if (ReadFile(this->handler, (void*)buffer, toRead, &bytesRead, NULL)) {
return bytesRead;
}
return 0;
}
int SerialPort::readSerialPortUntil(std::string* payload, std::string until) {
int untilLen = until.length(), len;
do {
char buffer[MAX_DATA_LENGTH];
int bytesRead = this->readSerialPort(buffer, MAX_DATA_LENGTH);
if (bytesRead == 0) {
int endIndex = this->readBuffer.find(until);
if (endIndex != -1) {
int index = endIndex + untilLen;
*payload = this->readBuffer.substr(0, index);
this->readBuffer = this->readBuffer.substr(index);
}
return bytesRead;
}
this->readBuffer += std::string(buffer);
len = this->readBuffer.length();
} while (this->readBuffer.find(until) == std::string::npos);
int index = this->readBuffer.find(until) + untilLen;
*payload = this->readBuffer.substr(0, index);
this->readBuffer = this->readBuffer.substr(index);
return index;
}
// Sending provided buffer to serial port;
// returns true if succeed, false if not
bool SerialPort::writeSerialPort(const char* buffer, unsigned int buf_size) {
DWORD bytesSend;
if (!WriteFile(this->handler, (void*)buffer, buf_size, &bytesSend, 0)) {
ClearCommError(this->handler, &this->errors, &this->status);
return false;
}
return true;
}
bool SerialPort::writeSerialPort(std::string payload) {
return this->writeSerialPort(payload.c_str(), payload.length());
}
// Checking if serial port is connected
bool SerialPort::isConnected() {
if (!ClearCommError(this->handler, &this->errors, &this->status)) {
this->connected = false;
}
return this->connected;
}
void SerialPort::closeSerial() {
CloseHandle(this->handler);
}