ogg_page_reader.cpp

linux下的一款播放器

    return HXR_OK;
}

STDMETHODIMP COggPageReader::CloseDone(THIS_ HX_RESULT status)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::CloseDone(0x%08x)\n", 
                                status));
    return HXR_OK;
}

STDMETHODIMP COggPageReader::ReadDone(THIS_ HX_RESULT status, 
                                      IHXBuffer* pBuffer)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::ReadDone(0x%08x, %u)\n", 
                                status, (pBuffer) ? pBuffer->GetSize() : 0));

    // Check for HXR_CANCELLED status. This can happen if a Seek() is
    // issued while a Read() is pending. This case only seems to happen
    // with HTTP
    if ((HXR_CANCELLED == status) &&
        (rsReadPending == m_state))
    {
        ChangeState(rsSeekPending);
        return HXR_OK;
    }
    
    switch(m_state) {
    case rsReadPending: 
    {
        if (HXR_OK == status)
        {
            /* Handle data */
            UINT32 ulBytes = pBuffer->GetSize();
            
            m_ulFileObjectOffset += ulBytes;

            // We are at the end of the file if we get a short
            // read OR we have a seekable file and the current 
            // file object offset is >= the file size.
            BOOL bEOF = 
                ((pBuffer->GetSize() < DefaultReadSize) ||
                 (m_bSeekable && (m_ulFileObjectOffset >= m_ulFileSize)));

            char* buffer = ogg_sync_buffer(m_pOy, ulBytes);
            memcpy(buffer, pBuffer->GetBuffer(), ulBytes);
            ogg_sync_wrote(m_pOy, ulBytes);
            
            status = DoReadNextPage(bEOF);
        }
        else if (m_bEndOfFile)
        {
            // Dispatch an end of file error
            status = DispatchPage(HXR_AT_END, 0, 0, NULL);
        }
        else
        {
            status = DispatchPage(status, 0, 0, NULL);
        }
    } break;
    case rsSeekDuringPending:
        status = DoSeek(m_ulPendingSeekOffset);
        break;
    default:
        status = DispatchPage(HXR_UNEXPECTED, 0, 0, NULL);
    };

    if ((HXR_OK == status) && (rsSeekDuringPending == m_state))
    {
        status = DoSeek(m_ulPendingSeekOffset);
    }

    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::ReadDone() : done\n"));

    return HXR_OK;
}

STDMETHODIMP COggPageReader::WriteDone(THIS_ HX_RESULT status)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::WriteDone(0x%08x)\n", 
                                status));
    return HXR_UNEXPECTED;
}

STDMETHODIMP COggPageReader::SeekDone(THIS_ HX_RESULT status)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::SeekDone(0x%08x)\n", status));

    BOOL bDone = FALSE;
    BOOL bDispatchedError = FALSE;

    while(!bDone)
    {
        bDone = TRUE;
        if (HXR_OK == status)
        {
            switch(m_state) {
            case rsSeekPending:
                status = DoRead();
                break;
            case rsSeekDuringPending:
                status = DoSeek(m_ulPendingSeekOffset);
                break;
            default :
                status = HXR_UNEXPECTED;
                break;
            };
        }

        if (HXR_OK != status)
        {
            DispatchPage(status, 0, 0, NULL);

            status = HXR_OK;
            bDone = FALSE;
        }
    }

    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::SeekDone() : done\n"));
    return HXR_OK;
}

/*
 *      IHXFileStat methods
 */

STDMETHODIMP COggPageReader::StatDone(THIS_
                                      HX_RESULT status,
                                      UINT32 ulSize,
                                      UINT32 ulCreationTime,
                                      UINT32 ulAccessTime,
                                      UINT32 ulModificationTime,
                                      UINT32 ulMode)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::StatDone(0x%08x, %lu)\n", 
                                status, ulSize));

    if (HXR_OK == status)
    {
        m_ulFileSize = ulSize;

        HX_RESULT tmpRes = m_pFile->Advise(HX_FILEADVISE_RANDOMACCESS);
        if (m_ulFileSize && (HXR_ADVISE_PREFER_LINEAR != tmpRes))
        {
            m_bSeekable = TRUE;
        }

        ChangeState(rsReady);
    }
    else
    {
        ChangeState(rsStart);
    }

    if (m_pResponse)
    {
        m_pResponse->PageReaderInitDone(status);
    }

    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::StatDone() : done\n"));

    return HXR_OK;
}

#ifdef _DEBUG
static const char* z_pStateNames[] = {
    "rsStart",
    "rsInitPending",
    "rsStatPending",
    "rsReady",
    "rsSeekPending",
    "rsSeekDuringPending",
    "rsReadPending",
    "rsDispatchReadPageDone",
    "rsReadDuringDispatch"
};
#endif

void COggPageReader::ChangeState(ReaderState newState)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::ChangeState() : %s -> %s\n", 
                                z_pStateNames[m_state], 
                                z_pStateNames[newState]));
    m_state = newState;
}

HX_RESULT COggPageReader::DoReadNextPage(BOOL bEOF)
{
    DPRINTF(D_OGG_PAGE_READER, 
            ("COggPageReader::DoReadNextPage()\n"));

    HX_RESULT res = HXR_FAILED;
    BOOL bDone = FALSE;

    while(!bDone)
    {
        BOOL bRecalcDone = TRUE;

        if (m_bEndOfFile)
        {
            res = DispatchPage(HXR_AT_END, 0, 0, NULL);
        }
        else
        {
            ogg_page og;
            int err = ogg_sync_pageseek(m_pOy, &og);
            
            if (err < 0)
            {
                /* resyncing */
                DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoReadNextPage() : resyncing %d skipped\n",
                         -err));

                m_ulCurrentFileOffset += -err;
                DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoReadNextPage() : m_ulCurrentFileOffset = %u\n", m_ulCurrentFileOffset));
                
                if (m_bSeekable && (m_ulCurrentFileOffset >= m_ulFileSize))
                {
                    m_bEndOfFile = TRUE;
                }

                bRecalcDone = FALSE;
            }
            else if (err == 0)
            {
                DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoReadNextPage() : Need more data\n"));
                if (!bEOF)
                {
                    // Read more data from the file
                    res = DoRead();
                }
                else
                {
                    m_bEndOfFile = TRUE;
                    bRecalcDone = FALSE;
                }
            }
            else
            {
                DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoReadNextPage() : synced on %d byte page\n",
                         err));

                ULONG32 ulOffset = m_ulCurrentFileOffset;
                m_ulCurrentFileOffset += err;

                DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoReadNextPage() : 2 m_ulCurrentFileOffset = %u\n", m_ulCurrentFileOffset));

                if (m_bSeekable && (m_ulCurrentFileOffset >= m_ulFileSize))
                {
                    m_bEndOfFile = TRUE;
                }

                res = DispatchPage(HXR_OK, ulOffset, err, &og);
            }
        }

        if (bRecalcDone)
        {
            bDone = (rsReadDuringDispatch != m_state);
        }
    }

    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::DoReadNextPage() : done\n"));

    return res;
}

HX_RESULT COggPageReader::DoSeek(ULONG32 ulFileOffset)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::DoSeek(%lu)\n", 
                                ulFileOffset));

    ChangeState(rsSeekPending);

    m_ulCurrentFileOffset = ulFileOffset;
    m_ulFileObjectOffset = ulFileOffset;

    DPRINTF(D_OGG_PAGE_READER, 
                        ("COggPageReader::DoSeek() : m_ulCurrentFileOffset = %u\n", m_ulCurrentFileOffset));
    m_bEndOfFile = FALSE;
    ogg_sync_reset(m_pOy);

    return m_pFile->Seek(ulFileOffset, FALSE);
}

HX_RESULT COggPageReader::DoRead()
{
    ChangeState(rsReadPending);
    return m_pFile->Read(DefaultReadSize);
}

HX_RESULT COggPageReader::DispatchPage(HX_RESULT status,
                                       ULONG32 ulFileOffset, 
                                       UINT32 ulPageSize, 
                                       ogg_page* pOg)
{
    DPRINTF(D_OGG_PAGE_READER, ("COggPageReader::DispatchPage(%lu, %u)\n", 
                                ulFileOffset, ulPageSize));

    ChangeState(rsDispatchReadPageDone);
    if (m_pResponse)
    {
        m_pResponse->ReadNextPageDone(status, ulFileOffset, ulPageSize, pOg);
    }

    if (rsDispatchReadPageDone == m_state)
    {
        ChangeState(rsReady);
    }

    return HXR_OK;
}