c/c++ code for vb6 multithreading

[smkperu]

Hello The Trick,

I wrote a small win32 c/c++ dll which exports a function initvbruntime() based on your modMultiThreading module as follows:

#include "stdafx.h"
#include <ole2.h>
#include "vbsim1.h"
typedef long (__stdcall *pVBDllGetClassObject) (HINSTANCE Unknown1,long Unknown2,PVOID Unknown3_vbheader,REFCLSID, REFIID, LPVOID*);//HINSTANCE h  REFCLSID 
typedef long (__stdcall *pGetMem4) (PVOID src,PVOID dst);//,REFCLSID, REFIID, LPVOID*);//HINSTANCE h  REFCLSID 
pVBDllGetClassObject pv1;
pGetMem4 pRtlMoveMemory;
HANDLE vbHandle;
HANDLE msvbvmvbHandle;
IDispatch *IDisp=NULL;




// Exported function.
__declspec(dllexport) int initvbruntime(void)
{
	INT		vbDLLPointer;
	PVOID	VBLIBPointerThunRTMain;
	PVOID	VBLIBPointerVDGCO;
	HANDLE	VBThread;
	PVOID	VBLIBPointerDGCO;
    PVOID   ptr;
	 CLSID      clsid;
	 HRESULT	   hr,hr1;
	ULONG lOldProtect;
	msvbvmvbHandle=LoadLibrary("msvbvm60.dll");
	pRtlMoveMemory=(pGetMem4)GetProcAddress((struct HINSTANCE__ *)msvbvmvbHandle, "GetMem4");
	vbHandle = GetModuleHandle(NULL);//LoadLibrary(DLLName);	
	//VBLIBPointerDGCO = GetProcAddress(vbHandle,"DllGetClassObject");
	/* Load the VB DLL								*/
	//vbDLLPointer = *(int*)((int)VBLIBPointerDGCO + 2);																/* Get the Project Pointer						*/
	// Get e_lfanew
	pRtlMoveMemory((int*)((int)vbHandle + 0x3C),ptr);
    //GetMem4 ByVal hModule + &H3C, ptr
    // Get AddressOfEntryPoint
	pRtlMoveMemory(*(int*)((int)ptr) + 0x28 + vbHandle,ptr);//compilation error C2036: 'void *' : unknown size
    //GetMem4 ByVal ptr + &H28 + hModule, ptr
    // Get VBHeader
	pRtlMoveMemory(ptr + vbHandle + 1,VBLIBPointerDGCO);//compilation error C2110: cannot add two pointers


     // Allow to write to that page
    VirtualProtect(VBLIBPointerDGCO, 0x64, PAGE_EXECUTE_READWRITE, &lOldProtect);
    
     // 'Remove Sub Main
    //ptr = mpVbHeader + &H2C
    //GetMem4 0&, ByVal ptr ' 'AddressOf mymain
    pRtlMoveMemory(VBLIBPointerDGCO + 0x2C,0);//compilation  error C2036: 'void *' : unknown size
    VirtualProtect(VBLIBPointerDGCO, 0x64, lOldProtect, 0);



    //GetMem4 ByVal ptr + hModule + 1, GetVBHeader
	//msvbvmvbHandle=LoadLibrary("msvbvm60.dll");
	VBLIBPointerThunRTMain = GetProcAddress((struct HINSTANCE__ *)msvbvmvbHandle,"ThunRTMain");								/* Get the VB Runtime Initialization Pointer	*/
    pv1=(pVBDllGetClassObject)GetProcAddress((struct HINSTANCE__ *)msvbvmvbHandle, "VBDllGetClassObject");

	try
{
hr1=	pv1((struct HINSTANCE__ *)vbHandle,0, VBLIBPointerDGCO,clsid, IID_IDispatch, (LPVOID *)&IDisp);
catch(...)
{
	if( FAILED( hr1 ) )
{
MessageBox(0,"\nVBDllGetClassObject failed",0,0);
}
}
    
	return 42;
}

In the above code I used GetMem4 and VBDllGetClassObject APIs of msvbvm60.dll


The code

1. finds the vbheader
2. removes sub main and
3. the vbheader is passed as input to VBDllGetClassObject() api for initializing vb runtime.


But I get following compilation errors when I try to build the dll which I mentioned in the above code:


Compiling...
vbsim1.cpp
E:\vbsim1\vbsim1.cpp(56) : error C2036: 'void *' : unknown size
E:\vbsim1\vbsim1.cpp(59) : error C2110: cannot add two pointers
E:\vbsim1\vbsim1.cpp(68) : error C2036: 'void *' : unknown size
Error executing cl.exe.

vbsim1.dll - 3 error(s), 0 warning(s)


Can you show how to use the GetMem4 and VBDllGetClassObject APIs of msvbvm60.dll properly without compilation errors
and use the dll to multithread in vb6.project link is attached.

Thanks