riff.cpp

linux下的一款播放器

                m_levelInfo[m_ulLevel].m_nextChunkOffset -= m_ulSizeDiff;

                m_ulChunkType = m_ulFindChunkId;

                if ( m_ulFindChunkId == LIST_CHUNK_ID )
                {
                    m_state = RS_GetListTypePending;
                    m_pFileObject->Read(sizeof(UINT32));
                }
                else
                {
                    m_state = RS_Ready;
                    m_pResponse->RIFFFindChunkDone(status,
                                                   m_ulChunkBodyLen - m_ulSizeDiff);
                }
                return status;
            }
            else
            {
                // Didn't find it, go to the next chunk.
                m_state = RS_ChunkBodySeekPending;
                m_ulSeekOffset = m_ulCurOffset + GetLong(&buf[4]);

                /* Are we at the end of .rm file */
                if ( m_ulSeekOffset == m_ulCurOffset &&
                     m_ulFileType != RIFF_FILE_MAGIC_NUMBER &&
                     m_ulFileType != IFF_FILE_MAGIC_NUMBER )
                {
                    m_pResponse->RIFFFindChunkDone(HXR_FAILED, 0);
                    return HXR_OK;
                }

                if ( m_ulFileType == RIFF_FILE_MAGIC_NUMBER ||
                     m_ulFileType == IFF_FILE_MAGIC_NUMBER )
                {
                    // Make sure the seek offset is aligned(2 bytes)
                    uRem = (UINT16)(m_ulSeekOffset % 2);
                    if ( uRem != 0 )
                    {
                        m_ulSeekOffset += 1;
                    }
                }

                m_ulSeekOffset -= m_ulSizeDiff;

                if ( m_ulSeekOffset == m_ulCurOffset )
                {
                    m_state = RS_ChunkHeaderReadPending;
                    return m_pFileObject->Read(sizeof(UINT32) * 2);
                }
                m_state = RS_ChunkBodySeekPending;
                return m_pFileObject->Seek(m_ulSeekOffset, FALSE);
            }
        case RS_GetListTypePending:
            if ( len != sizeof(UINT32) )
            {
                m_state = RS_Ready;
                m_pResponse->RIFFFindChunkDone(HXR_FAILED, 0);
                return HXR_UNEXPECTED;
            }

            m_ulChunkSubType = getlong(buf);
            m_state = RS_Ready;
            m_pResponse->RIFFFindChunkDone(status, m_ulChunkBodyLen);
            return HXR_OK;
        case RS_ReadChunkHeaderPending:
            {
                if ( HXR_OK != status )
                {
                    m_state = RS_Ready;
                    m_pResponse->RIFFGetChunkDone(HXR_FAILED, 0, NULL);
                    return HXR_OK;
                }

                m_ulGetChunkType = (UINT32)getlong(buf);
                m_state = RS_ReadChunkBodyPending;
                LONG32 baseLen = GetLong(&buf[4]);

                if ( (m_ulFileType == RIFF_FILE_MAGIC_NUMBER) &&
                     (m_ulGetChunkType == (UINT32)0) )
                {
                    m_state = RS_Ready;
                    m_pResponse->RIFFGetChunkDone(HXR_FAILED, 0, NULL);
                    return HXR_OK;
                }
                if ( baseLen == 0 )
                {
                    m_state = RS_Ready;
                    m_pResponse->RIFFGetChunkDone(HXR_OK, m_ulGetChunkType, NULL);
                    return HXR_OK;
                }

                HX_RESULT resultOfRead = HXR_OK;

#ifdef CHUNK_READ_SIZE_LIMIT
                // If the chunk is greater than MAX_READ_SIZE, we break the
                // read into smaller portions to improve performance under the
                // Simple File System:
                if (baseLen > MAX_READ_SIZE)
                {
                    IHXCommonClassFactory* pClassFactory = NULL;

                    if (m_pContext && SUCCEEDED(m_pContext->QueryInterface(IID_IHXCommonClassFactory,
                                                                          (void**) &pClassFactory)))
                    {
                        pClassFactory->CreateInstance(IID_IHXBuffer, (void**) &m_pReassemblyBuffer);
                    }

                    if (m_pReassemblyBuffer)
                    {
                        m_pReassemblyBuffer->SetSize(baseLen);

                        m_ulChunkBytesRead = 0;
                        m_ulChunkSize = baseLen;

                        // Here we munge baselen in the interests of code
                        // simplicity:
                        baseLen = MAX_READ_SIZE;
                    }
                }
#endif // CHUNK_READ_SIZE_LIMIT

                if ( m_ulFileType == RIFF_FILE_MAGIC_NUMBER ||
                     m_ulFileType == IFF_FILE_MAGIC_NUMBER )
                {
                    // Make sure the chunk is aligned(2 bytes)
                    uRem = (UINT16)((baseLen) % 2);

                    //NOTE: if m_ulCurOffset is greater than 0x7FFFFFFF, GetLong
                    // returns a negative number.  Any negative number % 2 (at
                    // least in Windows) returns 0 or -1, and ((UINT16)-1) == 0xFFFF
                    // so uRem thus can be one of the following: {0, 1, 0xFFFF}.
                    // The following if() conditional will, however, still work as
                    // expected:
                    if ( uRem != 0 )
                    {
                        m_ulFileSpecifiedReadSize = baseLen;
                        resultOfRead = m_pFileObject->Read(baseLen+1);
                    }
                    else
                    {
                        m_ulFileSpecifiedReadSize = baseLen;
                        resultOfRead = m_pFileObject->Read(baseLen);
                    }
                }
                else
                {
                    m_ulFileSpecifiedReadSize = baseLen;
                    resultOfRead = m_pFileObject->Read(baseLen);
                }
                return resultOfRead;
            }
        case RS_ReadChunkBodyPending:
#ifdef CHUNK_READ_SIZE_LIMIT
            if (m_pReassemblyBuffer)
            {
                BYTE* pAssemblyStart = m_pReassemblyBuffer->GetBuffer();
                HX_ASSERT(pAssemblyStart);

                HX_ASSERT(m_ulChunkSize - m_ulChunkBytesRead >= pBuffer->GetSize());
                UINT32 ulBytesToCopy = pBuffer->GetSize();
                if (pBuffer->GetSize() > m_ulChunkSize - m_ulChunkBytesRead)
                    ulBytesToCopy = m_ulChunkSize - m_ulChunkBytesRead;
                memcpy(pAssemblyStart + m_ulChunkBytesRead, pBuffer->GetBuffer(), /* Flawfinder: ignore */
                       ulBytesToCopy);
                m_ulChunkBytesRead += pBuffer->GetSize();

                if (m_ulChunkBytesRead == m_ulChunkSize || FAILED(status) ||
                    pBuffer->GetSize() == 0)
                {
                    m_state = RS_Ready;
                    IHXBuffer* pOldBuffer = m_pReassemblyBuffer;
                    m_pReassemblyBuffer = NULL;
                    m_pResponse->RIFFGetChunkDone(status, m_ulGetChunkType, pOldBuffer);
                    HX_RELEASE(pOldBuffer);
                    return HXR_OK;
                }
                else
                {
                    UINT32 baseLen = m_ulChunkSize - m_ulChunkBytesRead;

                    if (baseLen > MAX_READ_SIZE)
                    {
                        baseLen = MAX_READ_SIZE;
                    }

                    HX_RESULT resultOfRead = HXR_OK;

                    if ( m_ulFileType == RIFF_FILE_MAGIC_NUMBER ||
                         m_ulFileType == IFF_FILE_MAGIC_NUMBER )
                    {
                        // Make sure the chunk is aligned(2 bytes)
                        uRem = (UINT16)((baseLen) % 2);

                        //NOTE: if m_ulCurOffset is greater than 0x7FFFFFFF, GetLong
                        // returns a negative number.  Any negative number % 2 (at
                        // least in Windows) returns 0 or -1, and ((UINT16)-1) == 0xFFFF
                        // so uRem thus can be one of the following: {0, 1, 0xFFFF}.
                        // The following if() conditional will, however, still work as
                        // expected:
                        if ( uRem != 0 )
                        {
                            m_ulFileSpecifiedReadSize = baseLen;
                            resultOfRead = m_pFileObject->Read(baseLen+1);
                        }
                        else
                        {
                            m_ulFileSpecifiedReadSize = baseLen;
                            resultOfRead = m_pFileObject->Read(baseLen);
                        }
                    }
                    else
                    {
                        m_ulFileSpecifiedReadSize = baseLen;
                        resultOfRead = m_pFileObject->Read(baseLen);
                    }
                    return resultOfRead;
                }
            }
#endif // CHUNK_READ_SIZE_LIMIT

            m_state = RS_Ready;
            m_pResponse->RIFFGetChunkDone(status, m_ulGetChunkType, pBuffer);
            return HXR_OK;
        case RS_DataReadPending:
            m_state = RS_Ready;
            return m_pResponse->RIFFReadDone(status, pBuffer);
        default:
            //m_state = RS_Ready;
            return HXR_UNEXPECTED;
    }
    return status;
}

STDMETHODIMP
CRIFFReader::SeekDone(HX_RESULT status)
{
    /* This may happen in HTTP streaming when the file system
     * is in still a seeking mode when the next seek is issued.
     * The file system will then call SeekDone with a status of
     * HXR_CANCELLED for the pending seek.
     */
    if ( status == HXR_CANCELLED )
    {
        return HXR_OK;
    }

    if ( status == HXR_OK )
    {
        m_ulCurOffset = m_ulSeekOffset;
    }

    HX_RESULT result = HXR_OK;

    switch ( m_state )
    {
        case RS_ChunkBodySeekPending:
            m_state = RS_ChunkHeaderReadPending;
            result = m_pFileObject->Read(sizeof(UINT32) + sizeof(UINT32));
            return(HXR_OK == status? result:status);
        case RS_FileStartSeekPending:
            m_state = RS_ChunkHeaderReadPending;
            result = m_pFileObject->Read(sizeof(UINT32) + sizeof(UINT32));
            return(HXR_OK == status? result:status);
        case RS_AscendSeekPending:
            m_state = RS_Ready;
            result = m_pResponse->RIFFAscendDone(status);
            return(HXR_OK == status? result:status);
        case RS_UserSeekPending:
            m_state = RS_Ready;
            result = m_pResponse->RIFFSeekDone(status);
            return(HXR_OK == status? result:status);
        default:
            return HXR_UNEXPECTED;
    }
}

HX_RESULT
CRIFFReader::Seek(UINT32 offset, BOOL bRelative)
{
    m_ulSeekOffset = bRelative ?
                     m_ulCurOffset + offset :
                     m_ulThisChunkOffset + offset;
    m_state = RS_UserSeekPending;
    return m_pFileObject->Seek(m_ulSeekOffset, FALSE);
}

UINT32
CRIFFReader::IsThreadSafe()
{
    return HX_THREADSAFE_METHOD_FSR_READDONE;
}

HX_RESULT
CRIFFReader::FileSeek(UINT32 offset)
{
    m_ulSeekOffset = offset;
    m_state = RS_UserSeekPending;
    return m_pFileObject->Seek(m_ulSeekOffset, FALSE);
}

HX_RESULT
CRIFFReader::Descend()
{
    if ( m_ulLevel > 0 && m_ulChunkType != LIST_CHUNK_ID )
    {
        m_pResponse->RIFFDescendDone(HXR_FAILED);
        return HXR_UNEXPECTED;
    }

    m_ulLevel++;
    m_levelInfo[m_ulLevel].m_startOffset = m_ulCurOffset;
    m_levelInfo[m_ulLevel].started     = FALSE;

    return m_pResponse->RIFFDescendDone(HXR_OK);
}

HX_RESULT
CRIFFReader::Ascend()
{
    m_ulLevel--;
    m_state = RS_AscendSeekPending;
    if ( m_ulLevel == 0 )
        m_ulSeekOffset = 0;
    else
    {
        m_ulSeekOffset = m_levelInfo[m_ulLevel].m_nextChunkOffset;
    }

    m_pFileObject->Seek(m_ulSeekOffset, FALSE);
    return HXR_NOTIMPL;
}

STDMETHODIMP
CRIFFReader::CloseDone(HX_RESULT status)
{
    return HXR_OK;
}

STDMETHODIMP
CRIFFReader::WriteDone(HX_RESULT status)
{
    return HXR_NOTIMPL;
}

/************************************************************************
 *  Method:
 *      IHXFileResponse::FileObjectReady
 *  Purpose:
 *      Notification interface provided by users of the IHXFileObject
 *      interface. This method is called by the IHXFileObject when the
 *      requested FileObject is ready. It may return NULL with
 *      HX_RESULT_FAIL if the requested filename did not exist in the
 *      same pool.
 */
STDMETHODIMP
CRIFFReader::FileObjectReady
(
HX_RESULT status,
IHXFileObject* pFileObject)
{
    return HXR_OK;
}

HX_RESULT
CRIFFReader::InternalClose()
{
    return HXR_OK;
}

HX_RESULT
CRIFFReader::Read(UINT32 len)
{
    // Read from the file on our owner's behalf

    m_state = RS_DataReadPending;
    return m_pFileObject->Read(len);
}

UINT32
CRIFFReader::GetListType()
{
    return m_ulChunkSubType;
}

UINT32
CRIFFReader::GetOffset()
{
    return m_ulCurOffset;
}

UINT32
CRIFFReader::FileType()
{
    return m_ulFileType;
}

UINT32
CRIFFReader::FileSubtype()
{
    return m_ulSubFileType;
}