datafsys.cpp

linux下的一款播放器

    
    if (m_pFileResponse) 
    {
	AddRef();
	IHXFileResponse* pResponse = m_pFileResponse;
	m_pFileResponse = 0;
	pResponse->CloseDone(HXR_OK);
	pResponse->Release();
	Release();
    }

    return HXR_OK;
}

/************************************************************************
 *  Method:
 *	IHXFileObject::Read
 *  Purpose:
 *	Reads a buffer of data of the specified length from the file
 *	and asynchronously returns it to the caller via the 
 *	IHXFileResponse interface passed in to Init.
 */
STDMETHODIMP DataFileObject::Read(ULONG32 ulCount)
{
    HX_RESULT hResult = HXR_OK;
    IHXBuffer* pBuffer = NULL;
    CHXNestedBuffer* pNestedBuffer = NULL;
    
    if (!m_pDataURL || m_ulFilePointer == m_pDataURL->GetSize())
    {
	m_pFileResponse->ReadDone(HXR_FAIL, 0);
	return HXR_OK;
    }

    // Don't read off the end of the buffer
    ulCount = min(ulCount, (m_pDataURL->GetSize() - m_ulFilePointer));

    // Create a nested buffer object
    hResult = CHXNestedBuffer::CreateObject(&pNestedBuffer);

    if (FAILED(hResult))
    {
	m_pFileResponse->ReadDone(hResult, 0);
	return HXR_OK;
    }

    // AddRef the object
    pNestedBuffer->AddRef();

    // Init the object
    hResult = pNestedBuffer->Init(m_pDataURL, m_ulFilePointer, ulCount);

    if (FAILED(hResult))
    {
	HX_RELEASE(pNestedBuffer);

	m_pFileResponse->ReadDone(hResult, 0);
	return HXR_OK;
    }

    // Query for the IHXBuffer interface
    hResult = pNestedBuffer->QueryInterface(IID_IHXBuffer, (void**)&pBuffer);
    HX_ASSERT(SUCCEEDED(hResult));

    m_ulFilePointer += ulCount;
    m_pFileResponse->ReadDone(HXR_OK, pBuffer);

    HX_RELEASE(pNestedBuffer);
    HX_RELEASE(pBuffer);

    return HXR_OK;
}

/************************************************************************
 *  Method:
 *	IHXFileObject::Write
 *  Purpose:
 *	Writes a buffer of data to the file and asynchronously notifies
 *	the caller via the IHXFileResponse interface passed in to Init,
 *	of the completeness of the operation.
 */
STDMETHODIMP DataFileObject::Write(IHXBuffer* pBuffer)
{
    return HXR_UNEXPECTED;
}

/************************************************************************
 *  Method:
 *	IHXFileObject::Seek
 *  Purpose:
 *	Seeks to an offset in the file and asynchronously notifies
 *	the caller via the IHXFileResponse interface passed in to Init,
 *	of the completeness of the operation.
 */
STDMETHODIMP DataFileObject::Seek(ULONG32 ulOffset, BOOL bRelative)
{
    HX_RESULT pnr = HXR_OK;
    
    if (!m_pDataURL)
    {
	m_pFileResponse->SeekDone(HXR_FAIL);
	return HXR_OK;
    }

    if (bRelative && ulOffset <= m_pDataURL->GetSize() - m_ulFilePointer)
    {
	m_ulFilePointer += ulOffset;
    }
    else if (!bRelative && ulOffset <= m_pDataURL->GetSize())
    {
	m_ulFilePointer = ulOffset;
    }
    else
    {
	pnr = HXR_FAIL;
    }
	
    m_pFileResponse->SeekDone(pnr);
    return pnr;
}

/************************************************************************
 * Method:
 *	IHXFileObject::Stat
 * Purpose:
 *	Collects information about the file that is returned to the
 *	caller in an IHXStat object
 */
STDMETHODIMP DataFileObject::Stat(IHXFileStatResponse* pFileStatResponse)
{
    HX_RESULT hResult = HXR_OK;

    if (!m_pDataURL)
    {
	hResult = HXR_FAIL;
	pFileStatResponse->StatDone(HXR_FAIL, 0, 0, 0, 0, 0);
    }
    else
    {
	pFileStatResponse->StatDone(HXR_OK, 
				    m_pDataURL->GetSize(),
				    0,
				    0,
				    0,
				    0);
    }

    return hResult;
}

/************************************************************************
 *  Method:
 *	IHXFileObject::Advise
 *  Purpose:
 *	To pass information to the File Object
 */
STDMETHODIMP DataFileObject::Advise(ULONG32 ulInfo)
{
    return HXR_UNEXPECTED;
}

// IHXFileExists interface
/************************************************************************
 *	Method:
 *	    IHXFileExists::DoesExist
 *	Purpose:
 */
STDMETHODIMP DataFileObject::DoesExist
(
    const char*             pPath, 
    IHXFileExistsResponse* pFileResponse
)
{
    pFileResponse->DoesExistDone(m_pDataURL ? TRUE : FALSE);
    return HXR_OK;
}

STDMETHODIMP DataFileObject::SetRequest
(
    IHXRequest* pRequest
)
{
    HX_RESULT hresult = HXR_OK;

    HX_RELEASE(m_pRequest);

    m_pRequest = pRequest;
    if (m_pRequest)
    {
	m_pRequest->AddRef();
    }

    const char* pURL;
    IHXValues* pHeaders = 0;
    IHXBuffer* pBuffer0 = 0;

    hresult = m_pRequest->GetURL(pURL);

    if (hresult != HXR_OK)
    {
	goto RequestError;
    }

    hresult = m_pClassFactory->CreateInstance(CLSID_IHXBuffer,
                                              (void**)&pBuffer0);

    hresult = ParseURL(pURL, m_MediaType, pBuffer0);
    if (SUCCEEDED(hresult))
    {
	m_pDataURL = pBuffer0;
	pBuffer0 = NULL;
    }


    /*
     * Now set the Response Headers
     */

    hresult = m_pClassFactory->CreateInstance(CLSID_IHXValues,
                                              (void**)&pHeaders);

    if (HXR_OK != hresult)
    {
	goto RequestError;
    }

    hresult = m_pClassFactory->CreateInstance(CLSID_IHXBuffer,
                                              (void**)&pBuffer0);

    if (HXR_OK != hresult)
    {
	goto RequestError;
    }

    pBuffer0->Set((Byte*)"no-cache", 9);
    pHeaders->SetPropertyCString("Pragma", pBuffer0);
    HX_RELEASE(pBuffer0);

    hresult = m_pClassFactory->CreateInstance(CLSID_IHXBuffer,
                                              (void**)&pBuffer0);
    if (HXR_OK != hresult)
    {
	goto RequestError;
    }

    pBuffer0->Set((Byte*)(const char*)m_MediaType, m_MediaType.GetLength()+1);

    pHeaders->SetPropertyCString("Content-Type", pBuffer0);
    HX_RELEASE(pBuffer0);

    m_pRequest->SetResponseHeaders(pHeaders);

RequestError:

    HX_RELEASE(pHeaders);
    HX_RELEASE(pBuffer0);
    return hresult;
}

STDMETHODIMP DataFileObject::GetRequest
(
    REF(IHXRequest*) pRequest
)
{
    pRequest = m_pRequest;

    if (pRequest)
    {
	pRequest->AddRef();
    }

    return HXR_OK;
}

/************************************************************************
 *	Method:
 *	    IHXFileMimeMapper::FindMimeType
 *	Purpose:
 */
STDMETHODIMP
DataFileObject::FindMimeType
(
    const char*		    /*IN*/  pURL, 
    IHXFileMimeMapperResponse* /*IN*/  pMimeMapperResponse
)
{
    HX_RESULT status = HXR_OK;
    CHXString mimeString;

    pMimeMapperResponse->AddRef();
    status = ParseURL(pURL, mimeString, NULL);
    status = pMimeMapperResponse->MimeTypeFound(status, (const char*)mimeString);
    pMimeMapperResponse->Release();

    return status;
}

/*
 *    Syntax       
 *    
 *      dataurl    := "data:" [ mediatype ] [ ";base64" ] "," data
 *      mediatype  := [ type "/" subtype ] *( ";" parameter )
 * 		- Matching of media type and subtype is ALWAYS 
 * 		  case-insensitive.
 * 	type	   := token
 * 	subtype	   := token
 *      parameter  := attribute "=" value     
 * 	attribute  := token
 *              - Matching of attributes is ALWAYS case-insensitive.
 * 	value	   := token | quoted-string
 * 	token	   := (alphanum | untspecials)?
 * 	quoted-string
 * 		   := """ (token | tspecials)? """
 * 	tspecials  := ";" | "/" | "?" | ":" | "@" | "=" | "(" | ")" | 
 * 		      "<" | ">" | "," | "\" | """ | "[" | "]"  
 * 	untspecials:= "-" | "_" | "." | "!" | "#" | "$" | "%" | "*" | "+"
 * 		      "|" | "`" | "~" | "'"
 *      data       := *urlchar
 * 	urlchar    := reserved | unreserved | escaped
 * 	reserved   := ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
 *                      "$" | ","      
 * 	unreserved := alphanum | mark
 * 	mark       := "-" | "_" | "." | "!" | "~" | "*" | "'" |
 *                      "(" | ")"      
 * 	escaped       = "%" hex hex
 * 	hex	   := digit | "A" | "B" | "C" | "D" | "E" | "F" |
 *                    "a" | "b" | "c" | "d" | "e" | "f"
 * 	alphanum   := alpha | digit      
 *	alpha      := lowalpha | upalpha
 * 	lowalpha   := "a" | "b" | "c" | "d" | "e" | "f" | "g" | "h" | "i" |
 * 		      "j" | "k" | "l" | "m" | "n" | "o" | "p" | "q" | "r" |
 * 		      "s" | "t" | "u" | "v" | "w" | "x" | "y" | "z"
 * 	upalpha	   := "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" |
 * 		      "J" | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" |
 * 		      "S" | "T" | "U" | "V" | "W" | "X" | "Y" | "Z"
 * 	digit	   := "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" |
 * 		      "8" | "9"   
 * 
 *   Attribute values in [RFC2045] are allowed to be either represented as
 *   tokens or as quoted strings. However, within a "data" URL, the
 *   "quoted-string" representation would be awkward, since the quote mark
 *   is itself not a valid urlchar. For this reason, parameter values
 *   should use the URL Escaped encoding instead of quoted string if the
 *   parameter values contain any "tspecial".
 *
 *   The ";base64" extension is distinguishable from a content-type
 *   parameter by the fact that it doesn't have a following "=" sign. 
 */

const char DATA_SCHEME[] = "data:";
#define DATA_SCHEME_SIZE (sizeof(DATA_SCHEME) - 1)
const char BASE64_TOKEN[] = ";base64";
#define BASE64_TOKEN_SIZE (sizeof(BASE64_TOKEN) - 1)

STDMETHODIMP DataFileObject::ParseURL(const char* pURL, 
				      CHXString& mimeString, 
				      IHXBuffer* pBuffer)
{
    HX_RESULT pnr = HXR_OK;
    UINT32 ulDataURLSize = strlen(pURL);
    const char* pCurrentChar = pURL;
    BOOL  bBase64 = FALSE;
    UINT32 ulDataLength = 0;
    char* pMimeString = NULL;
    const char* pMimeStringStart = NULL;
    const char* pMimeStringEnd = NULL;
    BOOL bHasMimeString = TRUE;

    // Skip any leading whitespace
    while (*pCurrentChar &&
	   *pCurrentChar < 0x20)
    {
	pCurrentChar++;
    }

    // pURL must begin with data scheme
    // dataurl    := "data:" [ mediatype ] [ ";base64" ] "," data
    if (strncasecmp(pCurrentChar, DATA_SCHEME, DATA_SCHEME_SIZE))
    {
	pnr = HXR_FAIL;
	goto exit;
    }
    else
    {
	pCurrentChar += DATA_SCHEME_SIZE;
    }

    // The URL may begin with "data:", "data:/", or "data://"
    if (*pCurrentChar == '/')
    {
	pCurrentChar++;
    }
    if (*pCurrentChar == '/')
    {
	pCurrentChar++;
    }

    if (*pCurrentChar == ';' || *pCurrentChar == ',')
    {
	bHasMimeString = FALSE;
    }
    else
    {

	if (strncasecmp(pCurrentChar, BASE64_TOKEN, BASE64_TOKEN_SIZE))
	{
	    pMimeStringStart = pCurrentChar;
	    pMimeStringEnd = pCurrentChar;

	    // parse past mediatype
	    // mediatype  := [ type "/" subtype ] *( ";" parameter )

	    // walk past type
	    while (tokenChars[*pCurrentChar])    
	    {
		pCurrentChar++;
	    }

	    // this better be a '/'
	    if (*pCurrentChar != '/')
	    {
		pnr = HXR_FAIL;
		goto exit;
	    }
	    else
	    {
		pCurrentChar++;
	    }

	    // walk past subtype
	    while (tokenChars[*pCurrentChar])    
	    {
		pCurrentChar++;
	    }
	    pMimeStringEnd = pCurrentChar;

	    if (*pCurrentChar == ';')
	    {
		while (*pCurrentChar == ';')
		{
		    // check for base64
		    if (strncasecmp(pCurrentChar, BASE64_TOKEN, 
			BASE64_TOKEN_SIZE))
		    {
			pCurrentChar++; // step past the ';'
			
			// walk past the attribute
			while(tokenChars[*pCurrentChar])    {pCurrentChar++;}

			// this better be a '='
			if (*pCurrentChar != '=')
			{
			    pnr = HXR_FAIL;
			    goto exit;
			}
			else
			{
			    pCurrentChar++;
			}

			// walk past value
			// XXXJEFFA need to handle quoted-string
			while(tokenChars[*pCurrentChar])    
			{
			    pCurrentChar++;
			}
			pMimeStringEnd = pCurrentChar;
		    }
		    else
		    {
			bBase64 = TRUE;
			pCurrentChar += BASE64_TOKEN_SIZE;
			break;
		    }
		}
	    }
	}
	else
	{
	    bBase64 = TRUE;
	    bHasMimeString = FALSE;
	    pCurrentChar += BASE64_TOKEN_SIZE;
	}
    }

    if (bHasMimeString)
    {
	// copy the mime string into the parameter
	ulDataLength = (pMimeStringEnd - pMimeStringStart);
	pMimeString = mimeString.GetBuffer(ulDataLength + 1);
	strncpy(pMimeString, pMimeStringStart, ulDataLength); /* Flawfinder: ignore */
        pMimeString[ulDataLength] = '\0';
	mimeString.ReleaseBuffer(ulDataLength);
    }
    else
    {
        mimeString = "text/plain";
    }

    // should be a comma between mediatype and data
    if (*pCurrentChar != ',')
    {
	pnr = HXR_FAIL;
	goto exit;
    }
    else
    {
	pCurrentChar++;
    }

    if (pBuffer != NULL)
    {
	BYTE* pOutput = NULL;
	INT32 nLength = 0;

	// The rest is the data. It needs to be un-escaped and possibly
	// un-base64 encoded.
	if (bBase64)
	{
	    // Un-base64 encode the data
	    pBuffer->SetSize(ulDataURLSize - (pCurrentChar - pURL));
	    pOutput = (BYTE*)pBuffer->GetBuffer();
	    nLength = BinFrom64(pCurrentChar, pBuffer->GetSize(), pOutput);

	    if (nLength == -1)
	    {
		pBuffer->SetSize(0);
	    }
	    else
	    {
		pBuffer->SetSize(nLength);
	    }
	}
	else
	{
	    // Un-escape the data
	    pBuffer->SetSize(ulDataURLSize - (pCurrentChar - pURL));
	    pOutput = (BYTE*)pBuffer->GetBuffer();
	    nLength = URLUnescapeBuffer(pCurrentChar, 
		ulDataURLSize - (pCurrentChar - pURL), (char*)pOutput);
	    
	    if (nLength == -1)
	    {
		pBuffer->SetSize(0);
	    }
	    else
	    {
		pBuffer->SetSize(nLength);
	    }
	}
    }

exit:    
    return pnr;
}