Fast Track Visual C++ 6.0 Programming
(Publisher: John Wiley & Sons, Inc.)
Author(s): Steve Holzner
ISBN: 0471312908
Publication Date: 09/01/98

The code for ScannerView.h and ScannerView.cpp appears in Listing 7.1.

Listing 7.1 ScannerView.h and ScannerView.cpp

// ScannerView.h : interface of the CScannerView class
//
/////////////////////////////////////////////////////////////////////////////

#if
!defined(AFX_SCANNERVIEW_H__BFF33AA1_A398_11D1_887F_D42B07C10710__INCLUDED_)
#define AFX_SCANNERVIEW_H__BFF33AA1_A398_11D1_887F_D42B07C10710__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

class CScannerView : public CView
{
protected: // create from serialization only
    CScannerView();
    DECLARE_DYNCREATE(CScannerView)

// Attributes
public:
    CScannerDoc* GetDocument();

// Operations
public:

// Overrides
    // ClassWizard generated virtual function overrides
    //{{AFX_VIRTUAL(CScannerView)
    public:
    virtual void OnDraw(CDC* pDC);  // overridden to draw this view
    virtual BOOL PreCreateWindow(CREATESTRUCT& cs);
    protected:
    virtual BOOL OnPreparePrinting(CPrintInfo* pInfo);
    virtual void OnBeginPrinting(CDC* pDC, CPrintInfo* pInfo);
    virtual void OnEndPrinting(CDC* pDC, CPrintInfo* pInfo);
    //}}AFX_VIRTUAL

// Implementation
public:
    virtual ~CScannerView();
#ifdef _DEBUG

    virtual void AssertValid() const;
    virtual void Dump(CDumpContext& dc) const;
#endif

protected:

// Generated message map functions
protected:
    //{{AFX_MSG(CScannerView)
    afx_msg void OnFileScanmemory();
    //}}AFX_MSG
    DECLARE_MESSAGE_MAP()
};

#ifndef _DEBUG  // debug version in ScannerView.cpp
inline CScannerDoc* CScannerView::GetDocument()
   { return (CScannerDoc*)m_pDocument; }
#endif

/////////////////////////////////////////////////////////////////////////////

//{{AFX_INSERT_LOCATION}}
// Microsoft Visual C++ will insert additional declarations immediately
before the previous line.

#endif //
!defined(AFX_SCANNERVIEW_H__BFF33AA1_A398_11D1_887F_D42B07C10710__INCLUDED_)


// ScannerView.cpp : implementation of the CScannerView class
//

#include “stdafx.h”
#include “Scanner.h”

#include “ScannerDoc.h”
#include “ScannerView.h”

#ifdef _DEBUG
#define new DEBUG_NEW

#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CScannerView

IMPLEMENT_DYNCREATE(CScannerView, CView)

BEGIN_MESSAGE_MAP(CScannerView, CView)
    //{{AFX_MSG_MAP(CScannerView)
    ON_COMMAND(ID_FILE_SCANMEMORY, OnFileScanmemory)
    //}}AFX_MSG_MAP
    // Standard printing commands
    ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
    ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
    ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CScannerView construction/destruction

CScannerView::CScannerView()
{
    // TODO: add construction code here

}

CScannerView::~CScannerView()
{
}

BOOL CScannerView::PreCreateWindow(CREATESTRUCT& cs)
{
    // TODO: Modify the Window class or styles here by modifying
    //  the CREATESTRUCT cs

    return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CScannerView drawing

void CScannerView::OnDraw(CDC* pDC)
{
    CScannerDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);

    TEXTMETRIC tm;

    pDC->GetTextMetrics(&tm);

    for(int loop_index = 0; loop_index <= pDoc->number_lines; loop_index++){
        pDC->TextOut(0, loop_index * tm.tmHeight, pDoc->text[loop_index]);
    }
}

/////////////////////////////////////////////////////////////////////////////
// CScannerView printing

BOOL CScannerView::OnPreparePrinting(CPrintInfo* pInfo)
{
    // default preparation
    return DoPreparePrinting(pInfo);
}

void CScannerView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
    // TODO: add extra initialization before printing
}

void CScannerView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
    // TODO: add cleanup after printing
}

/////////////////////////////////////////////////////////////////////////////
// CScannerView diagnostics

#ifdef _DEBUG

void CScannerView::AssertValid() const
{
    CView::AssertValid();
}

void CScannerView::Dump(CDumpContext& dc) const
{
    CView::Dump(dc);
}

CScannerDoc* CScannerView::GetDocument() // non-debug version is inline
{
    ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CScannerDoc)));
    return (CScannerDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CScannerView message handlers

void CScannerView::OnFileScanmemory()
{
    // TODO: Add your command handler code here

    CScannerDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);

    MEMORY_BASIC_INFORMATION MemoryBasicInfo;

    char CodeName[50], AddressString[50];

    LPVOID lpBase = NULL;

    for(LPVOID lpSearch = (LPVOID) 0x00400000; lpSearch < (LPVOID)
0xF0000000; lpSearch = (LPVOID) ((BYTE *) lpSearch + 4*1024)){

         VirtualQuery(lpSearch, &MemoryBasicInfo, sizeof(MemoryBasicInfo));

        if(lpBase != MemoryBasicInfo.AllocationBase){

            lpBase = MemoryBasicInfo.AllocationBase;

            if(GetModuleFileName((HINSTANCE)lpBase, CodeName, 50) != NULL){
                pDoc->text[pDoc->number_lines] = CodeName;
                sprintf(AddressString, “ is at location = %#x”, lpBase);
                pDoc->text[pDoc->number_lines++] += AddressString;
                Invalidate();
            }
        }
    }

}

We’ve seen a lot of memory handling already, but there’s more to come. In the next example, we let two processes communicate through shared memory, passing data from one to the other.

Memory-Mapped Files

In our next example, we work with memory-mapped files. A memory-mapped file is a region of memory, which can include the swap file, in which we place data that can be accessed by a number of programs. In this case, we type some data into a program.

           ----------------------------------------------
          |                                                    |
          |----------------------------------------------      |
          |  ---------------------------                       |
          | |Here's the data...        |       |
          | |                          |       |
          | |                          |       |
          | |                          |       |
          | |                          |       |
          | |                          |       |
          | |                          |       |
          |  --------------------------        |
          |                                    |
           ----------------------------------------------