magnification.dll Memory leak

Question

hello all

  i want to capture the screen with magnification.dll and I found a memory leak  

  please help me,thanks.

  Every time I click the button, the memory will increase by 10M. （::OnBnClickedCaptureButton）

   i found that t when i call "set_window_source_func_" he memory will add.

   maybe the system will malloc buff to store one frame, how can i free them?

  my code:

      

// kMagnifierWindowClass has to be "Magnifier" according to the Magnification
// API. The other strings can be anything.
static LPCTSTR kMagnifierHostClass   = L"ScreenCapturerWinMagnifierHost";
static LPCTSTR kHostWindowName       = L"MagnifierHost";
static LPCTSTR kMagnifierWindowClass = L"Magnifier";
static LPCTSTR kMagnifierWindowName  = L"MagnifierWindow";

typedef BOOL(WINAPI* MagImageScalingCallback)(HWND hwnd,
	void* srcdata,
	MAGIMAGEHEADER srcheader,
	void* destdata,
	MAGIMAGEHEADER destheader,
	RECT unclipped,
	RECT clipped,
	HRGN dirty);

typedef BOOL(WINAPI* MagInitializeFunc)(void);
typedef BOOL(WINAPI* MagUninitializeFunc)(void);
typedef BOOL(WINAPI* MagSetWindowSourceFunc)(HWND hwnd, RECT rect);
typedef BOOL(WINAPI* MagSetWindowFilterListFunc)(HWND hwnd,
	DWORD dwFilterMode,
	int count,
	HWND* pHWND);
typedef BOOL(WINAPI* MagSetImageScalingCallbackFunc)(
	HWND hwnd,
	MagImageScalingCallback callback);

HMODULE mag_lib_handle_ = NULL;
MagInitializeFunc mag_initialize_func_ = nullptr;
MagUninitializeFunc mag_uninitialize_func_ = nullptr;
MagSetWindowSourceFunc set_window_source_func_ = nullptr;
MagSetWindowFilterListFunc set_window_filter_list_func_ = nullptr;
MagSetImageScalingCallbackFunc set_image_scaling_callback_func_ = nullptr;



void Init()
{
	HMODULE hLib = LoadLibrary(L"dwmapi.dll");
	typedef HRESULT(WINAPI* CxDwmIsCompositionEnabled)(_Out_ BOOL* pfEnabled);
	CxDwmIsCompositionEnabled dce = reinterpret_cast<CxDwmIsCompositionEnabled>(
		GetProcAddress(hLib, "DwmIsCompositionEnabled"));
	BOOL result1;
	if (HRESULT err = dce(&result1) != S_OK) {
	}

	mag_lib_handle_ = LoadLibrary(L"Magnification.dll");
	if (!mag_lib_handle_)
		return;

	// Initialize Magnification API function pointers.
	mag_initialize_func_ = reinterpret_cast<MagInitializeFunc>(
		GetProcAddress(mag_lib_handle_, "MagInitialize"));
	mag_uninitialize_func_ = reinterpret_cast<MagUninitializeFunc>(
		GetProcAddress(mag_lib_handle_, "MagUninitialize"));
	set_window_source_func_ = reinterpret_cast<MagSetWindowSourceFunc>(
		GetProcAddress(mag_lib_handle_, "MagSetWindowSource"));
	set_window_filter_list_func_ = reinterpret_cast<MagSetWindowFilterListFunc>(
		GetProcAddress(mag_lib_handle_, "MagSetWindowFilterList"));
	set_image_scaling_callback_func_ =
		reinterpret_cast<MagSetImageScalingCallbackFunc>(
			GetProcAddress(mag_lib_handle_, "MagSetImageScalingCallback"));

	if (!mag_initialize_func_ || !mag_uninitialize_func_ ||
		!set_window_source_func_ || !set_window_filter_list_func_ ||
		!set_image_scaling_callback_func_) {
		return;
	}
}

void CMagCaptureDlg::OnBnClickedCaptureButton()
{
	//load magnification.dll and get the addr of func;
	Init();

	BOOL result = mag_initialize_func_();
	if (!result) {return;}

	// Create host dialog
	hostDlg = new CHostDlg();
	hostDlg->Create();
	// Create magnification window
	hwndMag = CreateWindow(WC_MAGNIFIER, TEXT("MagnifierWindow"),
		WS_CHILD | WS_VISIBLE,
		0, 0, m_ScreenX, m_ScreenY,
		hostDlg->GetSafeHwnd(), NULL, hInstance, NULL);
	if (hwndMag == NULL){return;}

	// Set the callback function
	if (!set_image_scaling_callback_func_(hwndMag, (MagImageScalingCallback)MagImageScaling)){
		return;
	}

	// Filter the main window
	if (!set_window_filter_list_func_(hwndMag, MW_FILTERMODE_EXCLUDE, 1, pFilterList)){
		return;
	}

	// Get the screen rectangle
	RECT sourceRect;
	sourceRect.top = 0;
	sourceRect.left = 0;
	sourceRect.right = m_ScreenX;
	sourceRect.bottom = m_ScreenY;

	// Prepare the flag for the callback function
	bCallbacked = FALSE;

	// Set window source to capture entire the desktop
	if (!set_window_source_func_(hwndMag, sourceRect)){
		return;
	}

	RECT rcZero = { 0,0,0,0 };
	// Set window source to capture entire the desktop
	if (!set_window_source_func_(hwndMag, rcZero))
	{
		return;
	}
	// TODO: Add your message handler code here
	// Free memory
	if (hostDlg != NULL){
		hostDlg->DestroyWindow();
		delete hostDlg;
	}
	if (hwndMag != NULL){
		::DestroyWindow(hwndMag);
		hwndMag = NULL;
	}

	if (pData != NULL) {
		delete pData;
		pData = NULL;
	}
	// Uninitialize the magnification
	bool bResult = mag_uninitialize_func_();

	FreeLibrary(mag_lib_handle_);
	mag_lib_handle_ = NULL;

	return;
}


BOOL MagImageScaling(HWND hwnd, void *srcdata, MAGIMAGEHEADER srcheader,
	void *destdata, MAGIMAGEHEADER destheader,
	RECT unclipped, RECT clipped, HRGN dirty)
{
	dwThreadId1 = GetCurrentThreadId();

	// Setup the bitmap info header
	bmif.biSize = sizeof(BITMAPINFOHEADER);
	bmif.biHeight = srcheader.height;
	bmif.biWidth = srcheader.width;
	bmif.biSizeImage = srcheader.cbSize;
	bmif.biPlanes = 1;
	bmif.biBitCount = (WORD)(bmif.biSizeImage / bmif.biHeight / bmif.biWidth * 8);
	bmif.biCompression = BI_RGB;

	// Prepare the buffer
	if (pData != NULL)
	{
		delete pData;
		pData = NULL;
	}
	pData = (BYTE*)malloc(bmif.biSizeImage);
	memcpy(pData, srcdata, bmif.biSizeImage);

	// The data bit is in top->bottom order, so we convert it to bottom->top order
	LONG lineSize = bmif.biWidth * bmif.biBitCount / 8;
	BYTE* pLineData = new BYTE[lineSize];
	BYTE* pStart;
	BYTE* pEnd;
	LONG lineStart = 0;
	LONG lineEnd = bmif.biHeight - 1;
	while (lineStart < lineEnd)
	{
		// Get the address of the swap line
		pStart = pData + (lineStart * lineSize);
		pEnd = pData + (lineEnd * lineSize);
		// Swap the top with the bottom
		memcpy(pLineData, pStart, lineSize);
		memcpy(pStart, pEnd, lineSize);
		memcpy(pEnd, pLineData, lineSize);

		// Adjust the line index
		lineStart++;
		lineEnd--;
	}
	delete[] pLineData;
	// Set the flag to say that the callback function is finished
	bCallbacked = TRUE;
	return TRUE;
}

Answer 1

i run into the same bug.

i can not solved the problem even i release the Magnification.dll.