C++ CAtlFile::Seek方法代码示例

//.........这里部分代码省略.........

    CAtlFile OutFile; 

	if (pData->m_pUrlInfo->m_dwDownloadFlags & HTTP_FLAG_NO_RESUME)
		DeleteFile(pData->m_pUrlInfo->m_DownloadFile); 

    hr = OutFile.Create(pData->m_pUrlInfo->m_DownloadFile, GENERIC_WRITE, 0, OPEN_ALWAYS);

    if (FAILED(hr))
    {
		_DBGAlert("**FAsyncDownload::FHttpDownloadTP::ProcessDownload: CreateFile failed: 0x%x, %d : %s\n", hr, GetLastError(), pData->m_pUrlInfo->m_DownloadFile); 
        return E_HTTP_WRITE_FILE; 
    }

    size_type llTotalRead = 0; 
    size_type llSizeMax = 0; 

	size_type ContentLen = FConn.GetContentLength(); 

	pData->m_pUrlInfo->m_ContentLength = ContentLen; 

    if (dwStatusCode == 206)
    {
        FString FStrRange = FConn.GetHeader(HTTP_QUERY_CONTENT_RANGE);
        
        if (FStrRange)
        {
           //Content-Range: bytes 21010-47021/47022
           const char* pszBytes = strstr(FStrRange, "bytes ");
           if (pszBytes != NULL)
           {
               pszBytes+=sizeof("bytes");
               LONGLONG llOffset = _strtoi64(pszBytes, NULL, 10); 
               hr = OutFile.Seek(llOffset, FILE_BEGIN); 
               llTotalRead = (size_type)llOffset; 
               if (FAILED(hr))
               {
                   _DBGAlert("**FAsyncDownload::FHttpDownloadTP::ProcessDownload: Seek to position %d failed: 0x%x, %d\n", hr, GetLastError()); 
               }

               const char* pszTotal = strchr(pszBytes, '/');
               if (pszTotal != NULL)
                   llSizeMax = _strtoi64(pszTotal + 1, NULL, 10); 
           }
        }
    }
	else
	{
		if (ContentLen > 0 && ContentLen == FileSize)
		{
			OutFile.Close();
			return S_OK; 
		}
	}

    if (llSizeMax == 0)
		llSizeMax = ContentLen;


    pData->pBindStatusCallback.OnProgress((ULONG)llTotalRead, (ULONG)llSizeMax, BINDSTATUS_BEGINDOWNLOADDATA, L"");

    DWORD dwBytesRead = 0; 
    for (;;)
    {
        if (!InternetReadFile(hReq, pBuffer, dwBufferSize, &dwBytesRead))
        {

//.........这里部分代码省略.........
					bFound = TRUE;	// Avoid fallback check below
					break;
				}

				nOffset += pFile->m_nSize;
			}
		}

		if ( ! bFound )		// No filename match, try exact size
		{
			nOffset = 0;
		//	const CString strExt = PathFindExtension( strSourceName );
			for ( POSITION pos = pDownload->m_pTorrent.m_pFiles.GetHeadPosition() ; pos ; )
			{
				pFile = pDownload->m_pTorrent.m_pFiles.GetNext( pos );

				if ( pFile->m_nSize == nSourceSize )	// && strExt == PathFindExtension( pFile->m_sPath )
				{
					DEBUG_ONLY( theApp.Message( MSG_DEBUG, _T("Merge Filesize Fallback") ) );
					nSourceOffset = nOffset;
				//	bFound = TRUE;
					break;
				}

				nOffset += pFile->m_nSize;
			}
		}
	}

	pLock.Unlock();

	const float fIncrement = fProgress / oList.size();

	const DWORD nBufferLength = 256 * 1024;		// Was 65536?

	// Read missing file fragments from selected file
	auto_array< BYTE > Buf( new BYTE [nBufferLength] );
	Fragments::List::const_iterator pItr = oList.begin();
	const Fragments::List::const_iterator pEnd = oList.end();
	for ( ; ! m_pEvent && pItr != pEnd ; ++pItr )
	{
		m_fProgress += fIncrement;		// Update tooltip

		QWORD qwLength = pItr->end() - pItr->begin();
		QWORD qwOffset = pItr->begin();

		// Check for overlapped fragments
		if ( qwOffset + qwLength <= nSourceOffset ||
			 nSourceOffset + nSourceSize <= qwOffset )
			 continue;	 // No overlaps

		// Calculate overlapped range end offset
		QWORD qwEnd = min( qwOffset + qwLength, nSourceOffset + nSourceSize );
		// Calculate overlapped range start offset
		qwOffset = max( qwOffset, nSourceOffset );
		// Calculate overlapped range length
		qwLength = qwEnd - qwOffset;
		// Calculate file offset if any
		QWORD qwFileOffset = ( qwOffset > nSourceOffset ) ? qwOffset - nSourceOffset : 0;
		if ( FAILED( oSource.Seek( qwFileOffset, FILE_BEGIN ) ) )
			continue;

		DWORD dwToRead;
		while ( ( dwToRead = (DWORD)min( qwLength, (QWORD)nBufferLength ) ) != 0 && ! m_pEvent )
		{
			DWORD dwReaded = 0;
			if ( SUCCEEDED( oSource.Read( Buf.get(), dwToRead, dwReaded ) ) && dwReaded )
			{
				pLock.Lock();

				if ( ! Downloads.Check( pDownload ) || pDownload->IsCompleted() || pDownload->IsMoving() )
					return;

				pDownload->SubmitData( qwOffset, Buf.get(), (QWORD)dwReaded );
				pLock.Unlock();
				qwOffset += (QWORD)dwReaded;
				qwLength -= (QWORD)dwReaded;
			}
			else
			{
				// File error or end of file. Non-Fatal
				break;
			}
		}

		pLock.Lock();

		if ( ! Downloads.Check( pDownload ) || pDownload->IsCompleted() || pDownload->IsMoving() )
			return;

		if ( bMergeValidation )
			pDownload->RunValidation();

		pDownload->SetModified();

		pLock.Unlock();
	}

//	m_bSuccess = true;
}

bool CTrueType::GetProperties(LPCTSTR pszFilePath, TTF_PROPERTIES* pProperties)
{
	CAtlFile FontFile;
	HRESULT hr = FontFile.Create(pszFilePath, GENERIC_READ, FILE_SHARE_READ, OPEN_EXISTING);
	if (FAILED(hr))
		return false;

	TTF_OFFSET_TABLE ttOffsetTable;
	FontFile.Read(&ttOffsetTable, sizeof(TTF_OFFSET_TABLE));
	ttOffsetTable.uNumOfTables = SWAPWORD(ttOffsetTable.uNumOfTables);
	ttOffsetTable.uMajorVersion = SWAPWORD(ttOffsetTable.uMajorVersion);
	ttOffsetTable.uMinorVersion = SWAPWORD(ttOffsetTable.uMinorVersion);

	// See if this is a true type font and the version is 1.0
	if (ttOffsetTable.uMajorVersion != 1 || ttOffsetTable.uMinorVersion != 0)
		return false;
	
	TTF_TABLE_DIRECTORY tblDir;
	TTF_TABLE_DIRECTORY tblName;
	TTF_TABLE_DIRECTORY tblOS2;
	bool bFoundNameTable = false;
	bool bFoundOS2Table = false;
	for (int i=0; i< ttOffsetTable.uNumOfTables; i++)
	{
		FontFile.Read(&tblDir, sizeof(TTF_TABLE_DIRECTORY));
		CString strName = CString(tblDir.szTag, 4);
		if (strName.IsEmpty())
			break;

		if (!strName.CompareNoCase("name"))
		{
			bFoundNameTable = true;
			tblName = tblDir;
			tblName.uLength = SWAPLONG(tblName.uLength);
			tblName.uOffset = SWAPLONG(tblName.uOffset);
		}
		else
		if (!strName.CompareNoCase("OS/2"))
		{
			bFoundOS2Table = true;
			tblOS2 = tblDir;
			tblOS2.uLength = SWAPLONG(tblOS2.uLength);
			tblOS2.uOffset = SWAPLONG(tblOS2.uOffset);
		}

		if (bFoundNameTable && bFoundOS2Table)
			break;
	}
	
	if (bFoundNameTable)
	{
		FontFile.Seek(tblName.uOffset, FILE_BEGIN);

		TTF_NAME_TABLE_HEADER ttNTHeader;
		FontFile.Read(&ttNTHeader, sizeof(TTF_NAME_TABLE_HEADER));
		ttNTHeader.uFSelector      = SWAPWORD(ttNTHeader.uFSelector);
		ttNTHeader.uNRCount        = SWAPWORD(ttNTHeader.uNRCount);
		ttNTHeader.uStorageOffset  = SWAPWORD(ttNTHeader.uStorageOffset);

		for (int i=0; i<ttNTHeader.uNRCount; i++)
		{
			TTF_NAME_RECORD ttRecord;
			FontFile.Read(&ttRecord, sizeof(TTF_NAME_RECORD));
			ttRecord.uPlatformID   = SWAPWORD(ttRecord.uPlatformID);
			ttRecord.uEncodingID   = SWAPWORD(ttRecord.uEncodingID);
			ttRecord.uLanguageID   = SWAPWORD(ttRecord.uLanguageID);
			ttRecord.uNameID       = SWAPWORD(ttRecord.uNameID);
			ttRecord.uStringLength = SWAPWORD(ttRecord.uStringLength);
			ttRecord.uStringOffset = SWAPWORD(ttRecord.uStringOffset);

			if (ttRecord.uPlatformID != 3) // Microsoft
				continue;

			ULONGLONG nPos = 0;
			FontFile.GetPosition(nPos);
			FontFile.Seek(tblName.uOffset + ttRecord.uStringOffset + ttNTHeader.uStorageOffset, FILE_BEGIN);

			int iUnicodeChars = (ttRecord.uStringLength + 1) / 2;
			WCHAR* pUnicodeBuffer = new WCHAR[iUnicodeChars];
			FontFile.Read(pUnicodeBuffer, ttRecord.uStringLength);
			for (int i = 0; i < iUnicodeChars; i++)
				pUnicodeBuffer[i] = SWAPWORD(pUnicodeBuffer[i]);

			CString strName = CString(pUnicodeBuffer, iUnicodeChars);
			delete [] pUnicodeBuffer;
			FontFile.Seek(nPos, FILE_BEGIN);
			
			if (strName.IsEmpty())
				continue;

			switch (ttRecord.uNameID)
			{
				case 1: // Font family
					pProperties->strFamily.IsEmpty() ? pProperties->strFamily = strName : void();
					break;
				case 0: // Copyright notice
					pProperties->strCopyright.IsEmpty() ? pProperties->strCopyright = strName : void();
					break;
				case 7: // Trademark notice
					pProperties->strTrademark.IsEmpty() ? pProperties->strTrademark = strName : void();
//.........这里部分代码省略.........