[x]
Posted via EE Mobile

Search, ask, and monitor your questions on the go with EE Mobile. Visit Experts Exchange from your mobile device and never be out of touch again.
Question
[x]
Attachment Details
[x]
The Solution Rating System

With so many solutions, how can you tell which solutions are most likely to help you and which ones are not? To provide you with a tool to use, we rate our solutions based on various elements that most accurately determine if a solution is a quality solution. To explain what factors affect the solution rating, here are the elements we take into consideration when formulating our solution rating.

  • The Grade of the Solution
  • The Zone Rank of the Expert Providing the Solution
  • The Number of Author and Expert Comments
  • The Number of Experts Contributing
  • The Feedback of the Community

Your Input Matters
Because of the way the system is set up, the most important variable in this equation is you. As a member of Experts Exchange, you are able to cast your vote on the quality of the solutions in regard to how complete, accurate, helpful and easy to understand each solution is. When you provide your feedback, each rating is adjusted accordingly. So, if you see a solution that has a poor rating that you think is a good solution, let us know by rating it. As you do, the rating will be adjusted and will become more accurate for other members of our site.

If you have any suggestions that you would like to make for our rating system, please ask a question in the Suggestions Zone of Community Support.

Thank you!
8.5

Memory Leaks found in an MFC / COM / GDI application (HTML thumbnail image capture class)

Asked by DrivenX in Windows ATL / WTL / COM Programming, Windows MFC Programming, C++ Programming Language

Tags: C++, MFC, COM, Detected memory leaks!, SelectObject DeleteObject MFC COM C++ GDI HDC CDC DeleteDC GetDC ReleaseDC

Hi, I'm new to Experts-Exchange and this would be my first question.  Thanks in advance, please let me know if the format of my question can be improved to make it easier for the experts :)

I am a beginner in using MFC and COM and I am following up on a windows application.  One of the features is to be able to generate an image from a URL.  I have included the code of the function in the thumbnail capture class (CCreateHTMLImage).  (The original source for this code can be found at http://www.codeproject.com/KB/IP/htmlimagecapture.aspx - I have modified the CreateImage function, integrating with IECapt's SaveSnapShot method found here http://iecapt.sourceforge.net/ ).

When the user chooses to generate a thumbnail capture of a webpage, the application will do the following routine inside a CView derived class:
m_pHTMLImage is a pointer set to NULL initially

            if(m_pHTMLImage == NULL) {
                  OutputDebugString("Initializing m_pHTMLImage\n");
                  m_pHTMLImage = new CCreateHTMLImage();
                  m_pHTMLImage->Create(this);
            }

            if(!m_pHTMLImage -> CreateImage(_T("http://")+URL, AppDirectory + _T("\\temp.jpg"), CSize(1024, 768), CSize(360,300)))
                  return;

            It will then call a function LoadPic(AppDirectory + _T("\\temp.jpg"));

LoadPic(CString PicPath)
{
      CFile file;
      if(!file.Open(PicPath, CFile::modeRead|CFile::shareDenyWrite|CFile::typeBinary))
            return FALSE;
      if(m_dwPicLen != 0)
            delete[] m_BPicData; //if pic already exists, clear and load new data
      m_dwPicLen = (DWORD)(file.GetLength());                                                
      if(!m_Pic.Load(file.GetFilePath()))
            return FALSE;
      m_bIsPic = TRUE; //set display mode to pic
      m_BPicData = new BYTE[m_dwPicLen];
      file.Read(m_BPicData, m_dwPicLen);
      file.Close();
      return TRUE;
}

the memory usage jumps from ~10,000K to ~100,000K, should it be using this much memory?
subsequent calls to this routine of generating an image will raise mem usage by ~10,000K
I only create one instance of CCreateHTMLImage and will do the following routine when the application closes in the CView class' destructor

      if(m_pHTMLImage) {  
            m_pHTMLImage->DestroyWindow();  
            delete m_pHTMLImage;  // EL
            m_pHTMLImage = NULL;  
      }

Are there any problems regarding the Allocation and Release of Interfaces or in Getting and Releasing/Deleting DCs in the CreateImage Function? would i have to delete or release hdcMain?

I have used PurifyPlus and I have attached the results as images.
The leaks seem to come from DLLs, does it mean that it is not related to the classes I am working on?

More recent debug results are from boundschecker.

I am also getting many many of the following errors when i generate a thumbnail
First-chance exception at 0x30195840 in czWeb.exe: 0x80000001: Not implemented.
First-chance exception at 0x30195196 in czWeb.exe: 0x80000001: Not implemented.
Any idea what could generate these errors ?

Any help would be greatly appreciated.  Please let me know if anything was unclear or if you need more information

Thanks
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:
80:
81:
82:
83:
84:
85:
86:
87:
88:
89:
90:
91:
92:
93:
94:
95:
96:
97:
98:
99:
100:
101:
102:
103:
104:
105:
106:
107:
108:
109:
110:
111:
112:
113:
114:
115:
116:
117:
118:
119:
120:
121:
122:
123:
124:
125:
126:
127:
128:
129:
130:
131:
132:
133:
134:
135:
136:
137:
138:
139:
140:
141:
142:
143:
144:
145:
146:
147:
148:
149:
150:
151:
152:
153:
154:
155:
156:
157:
158:
159:
160:
161:
162:
163:
164:
165:
166:
167:
168:
169:
170:
171:
172:
173:
174:
175:
176:
177:
178:
179:
180:

BOOL CCreateHTMLImage::CreateImage(LPCTSTR szSrcFilename, LPCTSTR szDestFilename, CSize srcSize, CSize outputSize)
{
	USES_CONVERSION;
	ASSERT(GetSafeHwnd());
	ASSERT(IsWindow(GetSafeHwnd()));
	ASSERT(szSrcFilename);
	ASSERT(AfxIsValidString(szSrcFilename));
	ASSERT(szDestFilename);
	ASSERT(AfxIsValidString(szDestFilename));
 
	CRect rect(CPoint(0, 0), srcSize);
 
	//	The WebBrowswer window size must be set to our srcSize
	//	else it won't render everything
	MoveWindow(&rect);
	m_pBrowserWnd.MoveWindow(&rect);
 
	COleVariant	  vUrl(szSrcFilename, VT_BSTR),
				  vFlags(long(navNoHistory | navNoReadFromCache | navNoWriteToCache), VT_I4),
				  vNull(LPCTSTR(NULL), VT_BSTR);
	COleSafeArray vPostData;
 
	if (m_pBrowser->Navigate2(&vUrl, &vFlags, &vNull, &vPostData, &vNull) == S_OK)
		//	We have to pump messages to ensure the event handler (DocumentComplete)
		//	is called.
		RunModalLoop();
	else
		return FALSE;
 
//	We only get here when DocumentComplete has been called, which calls EndModalLoop
	//	and causes RunModalLoop to exit.
 
 
	IHTMLDocument3* pDocument3 = NULL;
        IHTMLDocument2* pDocument  = NULL;
        IHTMLElement2* pElement2   = NULL;
        IHTMLElement* pElement     = NULL;
        IViewObject2* pViewObject  = NULL;
        IDispatch* pDispatch       = NULL;
        //IDispatch* pWebBrowserDisp = NULL;
 
        HRESULT hr;
        long bodyHeight;
        long bodyWidth;
        long rootHeight;
        long rootWidth;
        long height;
        long width;
 
        hr = m_pBrowser->get_Document(&pDispatch);
		if (hr == S_OK) {  // Need to release pDispatch
 
			hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void**) &pDocument);
			if (hr == S_OK) {  // Need to release pDocument
 
				hr = pDocument->get_body(&pElement);
				if (hr == S_OK) {  // Need to release pElement
 
					hr = pElement->QueryInterface(IID_IHTMLElement2, (void**) &pElement2);
					if (hr == S_OK) {  // Need to release pElement2
 
						hr = pElement2->get_scrollHeight(&bodyHeight);
						if (FAILED(hr))
							return true;
 
						hr = pElement2->get_scrollWidth(&bodyWidth);
						if (FAILED(hr))
							return true;
 
						pElement2->Release();
					}
					pElement->Release();
				}
				pDocument->Release();
			}
 
			hr = pDispatch->QueryInterface(IID_IHTMLDocument3, (void**) &pDocument3);
			if (hr == S_OK) {  // Need to release pDocument3
 
				hr = pDocument3->get_documentElement(&pElement);
				if (hr == S_OK) {  // Need to release pElement
 
					hr = pElement->QueryInterface(IID_IHTMLElement2, (void**) &pElement2);
					if (hr == S_OK) {  // Need to release pElement2
 
						hr = pElement2->get_scrollHeight(&rootHeight);
						if (FAILED(hr))
							return true;
 
						hr = pElement2->get_scrollWidth(&rootWidth);
						if (FAILED(hr))
							return true;
						pElement2->Release();
					}
					pElement->Release();
				}
				pDocument3->Release();
			}
 
 
			width = bodyWidth;
			height = rootHeight > bodyHeight ? rootHeight : bodyHeight;
 
			MoveWindow(0, 0, width, height, TRUE);      
			::MoveWindow(m_pBrowserWnd.GetSafeHwnd(), 0, 0, width, height, TRUE);
 
			hr = m_pBrowser->QueryInterface(IID_IViewObject2, (void**) &pViewObject);
			if (hr == S_OK) {  // Need to release pViewObject
				BITMAPINFOHEADER bih;
				BITMAPINFO bi;
				RGBQUAD rgbquad;
 
				ZeroMemory(&bih, sizeof(BITMAPINFOHEADER));
				ZeroMemory(&rgbquad, sizeof(RGBQUAD));
 
				bih.biSize          = sizeof(BITMAPINFOHEADER);
				bih.biWidth         = width;
				bih.biHeight        = height;
				bih.biPlanes        = 1;
				bih.biBitCount      = 24;
				bih.biClrUsed       = 0;
				bih.biSizeImage     = 0;
				bih.biCompression   = BI_RGB;
				bih.biXPelsPerMeter = 0;
				bih.biYPelsPerMeter = 0;
 
				bi.bmiHeader = bih;
				bi.bmiColors[0] = rgbquad;
 
				CDC* dc = GetDC();
				HDC hdcMain = *dc;
 
				if (!hdcMain)
					return true;
 
				HDC hdcMem = CreateCompatibleDC(hdcMain);
 
				if (!hdcMem)
					return true;
 
				char* bitmapData = NULL;
				HBITMAP hBitmap = CreateDIBSection(hdcMain, &bi, DIB_RGB_COLORS, (void**)&bitmapData, NULL, 0);
 
				if (!hBitmap) {
					// TODO: cleanup
					return true;
				}
 
				// Save original bitmap, note this is needed to be reselected to preven GDI resource leak // EL
				HGDIOBJ oldHBitmap = GetCurrentObject(hdcMem, OBJ_BITMAP);
				if(oldHBitmap == NULL) {
					OutputDebugString("GetCurrentObj failed\n");
					return true;
				}
 
				SelectObject(hdcMem, hBitmap);
 
				RECTL rcBounds = { 0, 0, width, height };
				hr = pViewObject->Draw(DVASPECT_CONTENT, -1, NULL, NULL, hdcMain, hdcMem, &rcBounds, NULL, NULL, 0);
				if (SUCCEEDED(hr)) {
					CImage image;
					image.Create(outputSize.cx, outputSize.cy, 24);
					CImageDC imageDC(image);
					::StretchBlt(imageDC, 0, 0, outputSize.cx, outputSize.cy, hdcMem, 0, 0, width, height, SRCCOPY);
					//::BitBlt(imageDC, 0, 0, width, height, hdcMem, 0, 0, SRCCOPY);
					image.Save(szDestFilename);
				}
				
				SelectObject(hdcMem, oldHBitmap);
				DeleteObject(hBitmap);
				DeleteDC(hdcMem);
				//DeleteDC(hdcMain);
				ReleaseDC(dc);
				pViewObject->Release();
			}
			pDispatch->Release();
		}
		return true;
 
}
Attachments:
 
bcsummary.jpg (74 KB) (File Type Details) 
Summary of results from BoundsChecker
Summary of results from BoundsChecker
 
 
bc1.jpg (134 KB) (File Type Details) 
BC - Memory Leaks
BC - Memory Leaks
 
 
bc2.jpg (264 KB) (File Type Details) 
BC - Other Leaks
BC - Other Leaks
 
 
bc3.jpg (60 KB) (File Type Details) 
BC - Errors
BC - Errors
 
 
purify2.jpg (472 KB) (File Type Details) 
PurifyPlus Results, Memory leak information 1
PurifyPlus Results, Memory leak information 1
 
 
purify3.jpg (446 KB) (File Type Details) 
PurifyPlus Results, Memory leak information 2
PurifyPlus Results, Memory leak information 2
 
 
purify4.jpg (463 KB) (File Type Details) 
PurifyPlus Results, Memory leak information 3
PurifyPlus Results, Memory leak information 3
 
[+][-]01/31/08 01:51 PM, ID: 20791603Expert Comment

At Experts Exchange, members can ask their questions to thousands of technology professionals, also known as Experts. Experts compete and collaborate to answer those questions by leaving comments like this one.

Start your 30-day free trial to view this Expert Comment or ask the Experts your question.

 
[+][-]01/31/08 01:58 PM, ID: 20791671Accepted Solution

View this solution now by starting your 30-day free trial. Setting up your free trial is quick, easy, and secure. We will return you to this solution, unlocked, when you're done.

About this solution

Zones: Windows ATL / WTL / COM Programming, Windows MFC Programming, C++ Programming Language
Tags: C++, MFC, COM, Detected memory leaks!, SelectObject DeleteObject MFC COM C++ GDI HDC CDC DeleteDC GetDC ReleaseDC
Sign Up Now!
Solution Provided By: jkr
Participating Experts: 2
Solution Grade: A
 
[+][-]01/31/08 04:22 PM, ID: 20793002Author Comment

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 30-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]01/31/08 07:10 PM, ID: 20793786Expert Comment

At Experts Exchange, members can ask their questions to thousands of technology professionals, also known as Experts. Experts compete and collaborate to answer those questions by leaving comments like this one.

Start your 30-day free trial to view this Expert Comment or ask the Experts your question.

 
[+][-]01/31/08 10:39 PM, ID: 20794633Author Comment

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 30-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]02/01/08 12:03 AM, ID: 20794871Assisted Solution

Assisted solutions are selected by the member who asked the question as a comment that contributed to their question's solution.

Start your 30-day free trial to view this Assisted Solution or ask the Experts your question.

 
[+][-]02/01/08 11:16 AM, ID: 20799657Author Comment

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 30-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]02/01/08 01:51 PM, ID: 20801100Author Comment

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 30-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]02/04/08 04:31 PM, ID: 20819635Author Comment

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 30-day free trial to view this Author Comment or ask the Experts your question.

 
 
Loading Advertisement...
20091111-EE-VQP-89 / EE_QW_2_20070628