Re: Why C++ doesn't use the parent's class function? (C++ question) - C / C++ / MFC Discussion Boards

Re: Install IIS

gothic_coder29-May-10 0:39

gothic_coder

29-May-10 0:39

Thanks for your reply, But i intend to install IIS version 5.1..

Re: Install IIS

Hristo-Bojilov29-May-10 0:47

Hristo-Bojilov

29-May-10 0:47

I've found that for IIS 5.1 . Smile | :)

Life is a stage and we are all actors!

Re: Install IIS

gothic_coder29-May-10 0:53

gothic_coder

29-May-10 0:53

To be very frank, I don't see any help code in the link.. How do i do this in VC??

Re: Install IIS

gothic_coder3-Jun-10 0:17

gothic_coder

3-Jun-10 0:17

Does anyone know how to install IIS using Sysocmgr.exe?

Why C++ doesn't use the parent's class function? (C++ question)

Green Fuze28-May-10 21:10

Green Fuze

28-May-10 21:10

Hey everybody.

Here's a C++ question.

I have 2 classes:

template<typename T>
class A_template
{
public:
... other stuff ...

void operator = (T* other){ _obj = other; }


protected:
T* _x;
};
//-----------------------------------------------
class B : public A_template<C>
{
... some functions ...
};

Now, the problem is that if I have the following line of code:
C* x = CreateC();
B b;

b = x; // <--- compiler returns that there is no possible conversion, but it does, in A ! what am I doing wrong??

Thanks a lot !!! Smile | :)

Re: Why C++ doesn't use the parent's class function? (C++ question)

Green Fuze28-May-10 21:11

Green Fuze

28-May-10 21:11

Oh,
and the definition of B is:
class B : public A_template<c>.

Smile | :)

Re: Why C++ doesn't use the parent's class function? (C++ question)

eusto28-May-10 23:20

eusto

28-May-10 23:20

assignment operator works like the constructor when it comes to inheritance. You should read more about this.

Also read about:

<br />
using A<T>::operator =;<br />

which should be placed in the declaration of B

Re: Why C++ doesn't use the parent's class function? (C++ question)

Green Fuze29-May-10 1:33

Green Fuze

29-May-10 1:33

Thanks

I read about what you said, and I understand why the copy assignment is not being derived,
but I can't find anything about the "using A<t>::operator =;".

Can I tell c++ explicitly that I want to use the operator at the base class?

Re: Why C++ doesn't use the parent's class function? (C++ question)

eusto29-May-10 8:44

eusto

29-May-10 8:44

just put that line in your B implementation and it should work

problem with creating model-less dialog as a child of CFormView

m_code28-May-10 18:54

m_code

28-May-10 18:54

Hi,
I want to create a model-less dialog as a child of CFormView class.
what I did is as follow :

m_pDlg = new CMyDlg(this);
if(! m_pDlg->Create(IDD_DIALOG_DIAGRAM, this))
{
	::AfxMessageBox(L"An unknown error occurred while creating the window.");
	return;
}

I have created a Dialog with the ID of IDD_DIALOG_DIAGRAMbut in my resource editor And also I override the necessary methods to have model-less dialog But It always fail.
When I trace the dialog creation note that the

BOOL bResult = CreateIndirect(hTemplate, pParentWnd, hInst);

returns the error.
What is my problem?

Re: problem with creating model-less dialog as a child of CFormView

Richard MacCutchan28-May-10 22:26

Richard MacCutchan

28-May-10 22:26

Check the template of your dialog is correct, lso your CMyDlg constructor. Perhaps you should post the code for both parts here.

It's time for a new signature.

Re: problem with creating model-less dialog as a child of CFormView

m_code29-May-10 8:39

m_code

29-May-10 8:39

thanks I found the mistake the uninitialized RichEdit was causing the error.

about Hook WriteProcessMemory

rockago28-May-10 12:30

rockago

28-May-10 12:30

Who can tell me how to use the "Detours" to Hook WriteProcessMemory?
I want to get WriteProcessMemory the memory of information.

<br />
BOOL WINAPI MyWriteProcessMemory(<br />
  HANDLE hProcess,               // handle to process<br />
  LPVOID lpBaseAddress,          // base of memory area<br />
  LPVOID lpBuffer,               // data buffer<br />
  DWORD nSize,                   // number of bytes to write<br />
  LPDWORD lpNumberOfBytesWritten // number of bytes written<br />
);<br />
DETOUR_TRAMPOLINE(BOOL WINAPI CopyWriteProcessMemory(HANDLE, LPVOID, LPVOID, DWORD, LPDWORD), WriteProcessMemory);<br />
BOOL WINAPI MyWriteProcessMemory(<br />
  HANDLE hProcess,               // handle to process<br />
  LPVOID lpBaseAddress,          // base of memory area<br />
  LPVOID lpBuffer,               // data buffer<br />
  DWORD nSize,                   // number of bytes to write<br />
  LPDWORD lpNumberOfBytesWritten) // number of bytes written<br />
{<br />
    BOOL nResult=WriteProcessMemory(hProcess,lpBaseAddress,lpBaseAddress,nSize,lpNumberOfBytesWritten);    //call origin function<br />
 MessageBoxA(NULL,(LPCTSTR)lpBaseAddress,"Hook!",MB_OK);  <br />
return nResult;<br />
}<br />

this's my code ,but is not work. Frown | :(

Re: about Hook WriteProcessMemory

Garth J Lancaster28-May-10 14:02

Garth J Lancaster

28-May-10 14:02

rockago wrote:
but is not work

what exactely do you mean ?? - what are the signs, symptoms and/or error codes - we cant read your mind and formulate an answer based on not knowing what 'not working' means

'g'

Re: about Hook WriteProcessMemory

rockago28-May-10 14:23

rockago

28-May-10 14:23

<br />
//.cpp<br />
#include "stdafx.h"<br />
#include "DetourDll.h"<br />
<br />
#include "detours.h"	//the main API header of detours<br />
<br />
#pragma comment(lib,"detours.lib")<br />
<br />
BOOL WINAPI MyWriteProcessMemory(<br />
HANDLE hProcess, // handle to process<br />
LPVOID lpBaseAddress, // base of memory area<br />
LPVOID lpBuffer, // data buffer<br />
DWORD nSize, // number of bytes to write<br />
LPDWORD lpNumberOfBytesWritten // number of bytes written<br />
);<br />
DETOUR_TRAMPOLINE(BOOL WINAPI CopyWriteProcessMemory(HANDLE, LPVOID, LPVOID, DWORD, LPDWORD), WriteProcessMemory);<br />
BOOL WINAPI MyWriteProcessMemory(<br />
HANDLE hProcess, // handle to process<br />
LPVOID lpBaseAddress, // base of memory area<br />
LPVOID lpBuffer, // data buffer<br />
DWORD nSize, // number of bytes to write<br />
LPDWORD lpNumberOfBytesWritten) // number of bytes written<br />
{<br />
BOOL nResult=WriteProcessMemory(hProcess,lpBaseAddress,lpBaseAddress,nSize,lpNumberOfBytesWritten); //call origin function<br />
MessageBoxA(NULL,(LPCTSTR)lpBaseAddress,"Hook!",MB_OK); <br />
return nResult;<br />
}<br />
<br />
BOOL APIENTRY DllMain( HANDLE hModule, <br />
                       DWORD  ul_reason_for_call, <br />
                       LPVOID lpReserved<br />
					 )<br />
{<br />
    switch (ul_reason_for_call)<br />
	{<br />
		case DLL_PROCESS_ATTACH:<br />
			OutputDebugString("Detour dll Load!");<br />
			DetourFunctionWithTrampoline((PBYTE)CopyWriteProcessMemory, (PBYTE)MyWriteProcessMemory);<br />
		//	DetourFunctionWithTrampoline((PBYTE)CopyMessageBoxW, (PBYTE)MyMessageBoxW);<br />
			break;<br />
		case DLL_THREAD_ATTACH:<br />
			break;<br />
		case DLL_THREAD_DETACH:<br />
			break;<br />
		case DLL_PROCESS_DETACH:<br />
			OutputDebugString("Detour dll Exit!");<br />
			DetourRemove((PBYTE)CopyWriteProcessMemory, (PBYTE)MyWriteProcessMemory);<br />
		//	DetourRemove((PBYTE)CopyMessageBoxW, (PBYTE)MyMessageBoxW);<br />
			break;<br />
    }<br />
    return TRUE;<br />
}<br />
<br />
<br />
LRESULT WINAPI MsgProc(int code, WPARAM wParam, LPARAM lParam)<br />
{<br />
	//note :on windows 2k ,the 1st paramter to CallNextHookEx can be NULL<br />
	//On win 98 ,it must be the hook handle<br />
	return(CallNextHookEx(NULL,code,wParam,lParam));<br />
}<br />
<br />
//.def<br />
EXPORTS<br />
;dll export functions<br />
	MsgProc<br />
<br />
//.h<br />
<br />
// The following ifdef block is the standard way of creating macros which make exporting <br />
// from a DLL simpler. All files within this DLL are compiled with the DETOURDLL_EXPORTS<br />
// symbol defined on the command line. this symbol should not be defined on any project<br />
// that uses this DLL. This way any other project whose source files include this file see <br />
// DETOURDLL_API functions as being imported from a DLL, wheras this DLL sees symbols<br />
// defined with this macro as being exported.<br />
#ifdef DETOURDLL_EXPORTS<br />
#define DETOURDLL_API __declspec(dllexport)<br />
#else<br />
#define DETOURDLL_API __declspec(dllimport)<br />
#endif<br />
<br />
LRESULT WINAPI MsgProc(int code, WPARAM wParam, LPARAM lParam);<br />

this's my all code.
When I use the "WriteProcessMemory" after the injection, but it won't execute "MessageBoxA"

Re: about Hook WriteProcessMemory

Garth J Lancaster28-May-10 15:07

Garth J Lancaster

28-May-10 15:07

well, your formatting sucks for a start .. I cant quite put my finger on whats wrong .. looking at examples, I cant help feel that this (your code),

BOOL WINAPI MyWriteProcessMemory(
HANDLE hProcess, // handle to process
LPVOID lpBaseAddress, // base of memory area
LPVOID lpBuffer, // data buffer
DWORD nSize, // number of bytes to write
LPDWORD lpNumberOfBytesWritten) // number of bytes written
{
BOOL nResult=WriteProcessMemory(hProcess,lpBaseAddress,lpBaseAddress,nSize,lpNumberOfBytesWritten); //call origin function
MessageBoxA(NULL,(LPCTSTR)lpBaseAddress,"Hook!",MB_OK); 
return nResult;
}

should be this :-

BOOL WINAPI MyWriteProcessMemory(
HANDLE hProcess, // handle to process
LPVOID lpBaseAddress, // base of memory area
LPVOID lpBuffer, // data buffer
DWORD nSize, // number of bytes to write
LPDWORD lpNumberOfBytesWritten) // number of bytes written
{
BOOL nResult=CopyWriteProcessMemory(hProcess,lpBaseAddress,lpBaseAddress,nSize,lpNumberOfBytesWritten); //call origin function
MessageBoxA(NULL,(LPCTSTR)lpBaseAddress,"Hook!",MB_OK); 
return nResult;
}

CopyWriteProcessMemory has replaced WriteProcessMemory so calling WriteProcessMemory I dont think will work. Ive seen 'Real_' used instead of 'Copy', to make it a bit more obvious .. ie instead of

CopyWriteProcessMemory you would have Real_WriteProcessMemory

Obviously that means you start with

DETOUR_TRAMPOLINE(BOOL WINAPI Real_WriteProcessMemory(HANDLE, LPVOID, LPVOID, DWORD, LPDWORD), WriteProcessMemory);

Other than that I cant spot anything dramatically wrong ..

You might want to compare your code with this http://code.google.com/p/dxhook/source/browse/trunk/dxhook.cpp?r=4[^] to see if it helps

'g'

Re: about Hook WriteProcessMemory

rockago28-May-10 21:48

rockago

28-May-10 21:48

thx.
But when I taked "WriteProcessMemory "to" Real_WriteProcessMemory", After injection into or unable to carry out "MessageBoxA." Frown | :(

Re: about Hook WriteProcessMemory

Garth J Lancaster28-May-10 22:27

Garth J Lancaster

28-May-10 22:27

so what does your code look like now ?

also, you should be aware of (from http://msdn.microsoft.com/en-us/library/ms681674(VS.85).aspx[^] )

"hProcess [in]
A handle to the process memory to be modified. The handle must have PROCESS_VM_WRITE and PROCESS_VM_OPERATION access to the process."

so you may not have some permissions to write to that memory -
as that page also says, you can do a call to GetLastError - these 2 pages may help

http://msdn.microsoft.com/en-us/library/ms679360(v=VS.85).aspx[^]

http://msdn.microsoft.com/en-us/library/ms680582(v=VS.85).aspx[^]

so see what the error code is.

Finally, have you checked that your process handle of the process you are trying to write to is valid ? (Im presuming somewhere else in your code you are doing an OpenProcess on the Process ID you are trying to write to)

'g'

Re: about Hook WriteProcessMemory

Richard MacCutchan28-May-10 22:22

Richard MacCutchan

28-May-10 22:22

rockago wrote:
MessageBoxA(NULL,(LPCTSTR)lpBaseAddress,"Hook!",MB_OK);

lpBaseAddress is a pointer to void, I have no idea what it is pointing to but unless it's a string of ASCII characters you cannot cast it to LPCTSTR and expect MessageBoxA() to work.

It's time for a new signature.

Re: about Hook WriteProcessMemory

Garth J Lancaster28-May-10 22:33

Garth J Lancaster

28-May-10 22:33

if thats what his issue is Ive been wasting my breath !!! oh well ..

Re: about Hook WriteProcessMemory

Richard MacCutchan28-May-10 23:09

Richard MacCutchan

28-May-10 23:09

I think a bit of lateral thinking and lots of guesswork is needed here. I only noticed that because he mentioned the MessageBox call in two posts. I've no idea what the rest of it is, or is supposed to be, doing.

It's time for a new signature.

Write a function to cause a thread to wait

Danzy8328-May-10 9:08

Danzy83

28-May-10 9:08

Hi, I have written a function to cause a thread to wait for a given time. But the problem is that If this function is called, I notice from task manager (in Windows) that the CPU Usage shoots up to 100 percent. But if I rather use the Windows function Sleep(), the CPU Usage falls back to around 2%, 3%, and 4%. The following is how I wrote the function, with the header file <time.h> included.

void Wait(clock_t milliseconds)
{
clock_t delay_time = milliseconds + clock();

while (delay_time > clock())
;

return;
}

I don't know why my CPU usage shoots up to 100% when I use this function rather than Windows Sleep() function. I don't want my application to assume the use of Windows. Please help.

Re: Write a function to cause a thread to wait

CPallini28-May-10 9:19

CPallini

28-May-10 9:19

Dan_K wrote:
that the CPU Usage shoots up to 100 percent

No wonder: you're using the CPU, aren't you?
That's not the best way to pause an application on a multitasking system.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Re: Write a function to cause a thread to wait

Luc Pattyn28-May-10 9:33

Luc Pattyn

28-May-10 9:33

You should upgrade your hardware. If you buy a dual-core system, it will become twice as efficient: the CPU load will be around 50%. Or go for a quad-core and see it sitting idle with a load of a mere 25%.

If you don't like that idea, you should either use a sleep function or a timer.

FWIW: you could do both to make absolutely sure.

Laugh | :laugh:

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

I only read formatted code with indentation, so please use PRE tags for code snippets.

I'm not participating in frackin' Q&A, so if you want my opinion, ask away in a real forum (or on my profile page).

Re: Write a function to cause a thread to wait

Cedric Moonen28-May-10 10:02

Cedric Moonen

28-May-10 10:02

Your CPU usage goes to 100% simply because you are actually doing something: the while loop and the checks are operations done by the CPU, and in your case without interruption, so the CPU is always busy.

Cédric Moonen
Software developer

Charting control [v3.0]
OpenGL game tutorial in C++

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