Linking a C++ project with a form project in visual studio - c++

Question

I have a CLR project that includes a form (Project1), and another General project (Project2) in visual studio, both are in C++ and they both work perfectly by themselves. I'm trying to link them, but I keep getting the following error as soon as the program starts:
Exception thrown at 0x77400A36 (ntdll.dll) in BrailleGUI.exe: 0xC0000005: ?>Access violation reading location 0x029905BB.
If there is a handler for this exception, the program may be safely continued.
I tried adding Project2 to the solution of Project1, I tried adding the .h and .cpp files of Project2 into Project1, I even tried just copying the code into the files that already exist in Project1. I still get the same error. Any ideas?
Thank you in advance, please let me know if you need more info.
Code:
Project2.h
#pragma once
#include <Windows.h>
#include <iostream>
#include <WbemCli.h>
#include <string>
#include <comutil.h>
#include <regex>
#pragma comment(lib, "comsuppw.lib")
#pragma comment (lib, "wbemuuid.lib")
int ReturnCOM();
int FindPort(char *com);
Project2.cpp
#include "ChipCommunication.h"
using namespace std;
int ReturnCOM(){
int COMNumber = 0;
HRESULT hRes = CoInitializeEx(NULL, COINIT_MULTITHREADED);
if (FAILED(hRes)){
cout << "Unable to CoInitialize";
return -1;
}
if ((FAILED(hRes = CoInitializeSecurity(NULL, -1, NULL, NULL, RPC_C_AUTHN_LEVEL_CONNECT, RPC_C_IMP_LEVEL_IMPERSONATE, NULL, EOAC_NONE, 0))))
{
cout << "Unable to initialize security: 0x" << std::hex << hRes << endl;
return -1;
}
IWbemLocator* pLocator = NULL;
if (FAILED(hRes = CoCreateInstance(CLSID_WbemLocator, NULL, CLSCTX_ALL, IID_PPV_ARGS(&pLocator)))){
cout << "Unable to create a WbemLocator: " << hRes << endl;
return -1;
}
IWbemServices* pService = NULL;
if (FAILED(hRes = pLocator->ConnectServer(L"root\\CIMV2", NULL, NULL, NULL, WBEM_FLAG_CONNECT_USE_MAX_WAIT, NULL, NULL, &pService))){
pLocator->Release();
cout << "Unable to connect to \"CIMV2\": " << hRes << endl;
return -1;
}
IEnumWbemClassObject* pEnumerator = NULL;
if (FAILED(hRes = pService->ExecQuery(L"WQL", L"SELECT * FROM Win32_PnPEntity", WBEM_FLAG_FORWARD_ONLY, NULL, &pEnumerator))){
pLocator->Release();
pService->Release();
cout << "Unable to retrive com ports" << hRes << endl;
return -1;
}
IWbemClassObject* clsObj = NULL;
int numElems;
while ((hRes = pEnumerator->Next(WBEM_INFINITE, 1, &clsObj, (ULONG*)&numElems)) != WBEM_S_FALSE){
if (FAILED(hRes))
break;
VARIANT vRet;
VARIANT DeviceName;
VariantInit(&vRet);
VariantInit(&DeviceName);
if (SUCCEEDED(clsObj->Get(L"PNPDeviceID", 0, &vRet, NULL, NULL)) && vRet.vt == VT_BSTR){
if (wcsstr(vRet.bstrVal, L"VID_0525&PID_A4A7") != NULL){
if (SUCCEEDED(clsObj->Get(L"Name", 0, &DeviceName, NULL, NULL)) && DeviceName.vt == VT_BSTR){
char* PointAtCOM = _com_util::ConvertBSTRToString(DeviceName.bstrVal);
COMNumber = FindPort(PointAtCOM);
delete[] PointAtCOM;
}
}
VariantClear(&vRet);
}
clsObj->Release();
}
pEnumerator->Release();
pService->Release();
pLocator->Release();
return COMNumber;
}
int FindPort(char *com){
int ComNumber = 0;
regex FindCOM("\\(COM([0-9]+)");
smatch NumberinString;
string DeviceName (com);
if (regex_search(DeviceName, NumberinString, FindCOM)){
DeviceName = NumberinString[1].str();
ComNumber = stoi (DeviceName);
}
return ComNumber;
}
Project1.h
#pragma once
#include <windows.h>
#include <iostream>
#include <sstream>
#include <msclr\marshal_cppstd.h>
int comNum;
std::ostringstream cmdCHIPStream;
std::string cmdCHIPString;
namespace BrailleGUI {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class MyForm : public System::Windows::Forms::Form
{
public:
MyForm(void)
{
InitializeComponent();
}
protected:
~MyForm()
{
if (components){
delete components;
}
}
private: System::Windows::Forms::Button^ button1;
protected:
private: System::Windows::Forms::Button^ button2;
private: System::Windows::Forms::Label^ label1;
private: System::Windows::Forms::TextBox^ textBox1;
private: System::Windows::Forms::Label^ label2;
private:
System::ComponentModel::Container ^components;
#pragma region Windows Form Designer generated code
...
Project1.cpp
#include "ChipCommunication.h"
#include "MyForm.h"
using namespace System;
using namespace System::Windows::Forms;
[STAThread]
void main(array<String^> ^ args) {
comNum = ReturnCOM();
std::cout << "ReturnCOM is " << comNum << std::endl;
if (comNum == -1) {
std::cout << "Translator not connected" << std::endl;
}
std::ostringstream comConStream;
std::string comConString;
comConStream << "mode com" << comNum << " BAUD=115200 PARITY=n DATA=8" << std::endl;
comConString = comConStream.str();
system(comConString.c_str());
Application::EnableVisualStyles();
Application::SetCompatibleTextRenderingDefault(false);
BrailleGUI::MyForm form;
Application::Run(%form);
}

Answer 1

I got it to work by removing the [StaThread] line in Project1.cpp and I replaced the _com_util::ConvertBSTRToString() function with one that I found here: https://www.codeproject.com/Articles/1969/BUG-in-com-util-ConvertStringToBSTR-and-com-util