www.pudn.com > BAV.v2.rar > MemFileObject.cpp, change:2005-08-20,size:2371b

#include "StdAfx.h" 
#include "MemFileObject.h" 
 
CMemFileObject::CMemFileObject(void) 
{ 
	m_eObjType	= BO_MEM_FILE; 
 
	m_hMapFile	= NULL; 
	m_pFile		= NULL; 
} 
 
CMemFileObject::CMemFileObject(CMemFileObject& cMemFileObj) 
{ 
	m_eObjType	= BO_MEM_FILE; 
 
	m_hFile		= INVALID_HANDLE_VALUE; 
	m_dwObjSize	= cMemFileObj.m_dwObjSize; 
	m_strObjName= cMemFileObj.m_strObjName; 
 
	m_hMapFile	= NULL; 
	m_pFile		= NULL; 
} 
 
CMemFileObject::~CMemFileObject(void) 
{ 
	if(m_pFile) 
		Close(); 
} 
 
 
bool CMemFileObject::Open(bool bScan) 
{ 
	if(!CFileObject::Open(bScan)) 
		return false; 
 
	DWORD dwProtect, dwDesiredAccess; 
	if(bScan) 
	{ 
		dwProtect		= PAGE_READONLY; 
		dwDesiredAccess	= FILE_MAP_READ; 
	} 
	else 
	{ 
		dwProtect		= PAGE_READWRITE; 
		dwDesiredAccess	= FILE_MAP_WRITE; 
	} 
 
	// TODO: If clean virus enlarge the file size, we need calculate and change the dwMaximumSizeLow value. 
	m_hMapFile = ::CreateFileMapping(m_hFile, NULL, dwProtect, 0, 0, NULL); 
	if(m_hMapFile==NULL) 
	{ 
		Close(); 
		return false; 
	} 
	m_pFile = static_cast<LPBYTE>( ::MapViewOfFile(m_hMapFile, dwDesiredAccess, 0, 0, NULL) ); 
	if(m_pFile==NULL) 
	{ 
		Close(); 
		return false; 
	} 
 
	return true; 
} 
 
bool CMemFileObject::Close() 
{ 
	if(m_pFile) 
	{ 
		::UnmapViewOfFile(m_pFile); 
		m_pFile = NULL; 
	} 
	if(m_hMapFile) 
	{ 
		::CloseHandle(m_hMapFile); 
		m_hMapFile = NULL; 
	} 
	return CFileObject::Close(); 
} 
 
bool CMemFileObject::Compare(IN INT nOffset, IN INT nSize, IN LPBYTE pSignature, IN BAV_SIGN_LOGIC_OPERATION eLogicOp) 
{ 
	return Compare(m_pFile+nOffset, nSize, pSignature, eLogicOp); 
} 
 
bool CMemFileObject::Compare(IN LPBYTE pData, IN INT nSize, IN LPBYTE pSignature, IN BAV_SIGN_LOGIC_OPERATION eLogicOp) 
{ 
	ASSERT(m_eObjType==BO_MEM_FILE); 
	ASSERT(nSize=MAX_SIGNATURE_LEN); 
 
	if(!IsOpened()) 
	{ 
		ASSERT(false); 
		return false; 
	} 
 
	// Signature position exceed the file size 
	if(pData<m_pFile || pData>(m_pFile+m_dwObjSize)) 
	{ 
		// not match 
		return false; 
	} 
 
	int nRet = memcmp(pData, pSignature, nSize); 
	switch(eLogicOp) 
	{ 
	case BL_EQUAL: 
		return nRet==0; 
	case BL_NOT_EQUAL: 
		return nRet!=0; 
	default: 
		ASSERT(false); 
	} 
 
	return false; 
} 
 
bool CMemFileObject::IsOpened() 
{ 
	return m_pFile!=NULL; 
} 
 
LPBYTE CMemFileObject::GetBuffer() 
{ 
	ASSERT(IsOpened()); 
	return m_pFile; 
}