OggFile.cpp

#include "StdAfx.h"
#include ".\oggfile.h"

COggFile::COggFile(IAsyncReader* pAsyncReader, HRESULT& hr)
        : CBaseSplitterFile(pAsyncReader, hr)
{
        if(FAILED(hr)) return;
        hr = Init();
}

HRESULT COggFile::Init()
{
        Seek(0);
        if(!Sync()) return E_FAIL;

        return S_OK;
}

bool COggFile::Sync(HANDLE hBreak)
{
        __int64 start = GetPos();

        DWORD dw;
        for(__int64 i = 0, j = hBreak ? GetLength() - start : 65536;
                i < j && S_OK == Read((BYTE*)&dw, sizeof(dw)) 
                        && ((i&0xffff) || !hBreak || WaitForSingleObject(hBreak, 0) != WAIT_OBJECT_0); 
                i++, Seek(start + i))
        {
                if(dw == 'SggO')
                {
                        Seek(start + i);
                        return(true);
                }
        }

        Seek(start);

        return(false);
}

bool COggFile::Read(OggPageHeader& hdr, HANDLE hBreak)
{
        return Sync(hBreak) && S_OK == Read((BYTE*)&hdr, sizeof(hdr)) && hdr.capture_pattern == 'SggO';
}

bool COggFile::Read(OggPage& page, bool fFull, HANDLE hBreak)
{
        memset(&page.m_hdr, 0, sizeof(page.m_hdr));
        page.m_lens.RemoveAll();
        page.SetSize(0);

        if(!Read(page.m_hdr, hBreak))
                return(false);

        int pagelen = 0, packetlen = 0;
        for(BYTE i = 0; i < page.m_hdr.number_page_segments; i++)
        {
                BYTE b;
        if(S_OK != Read(&b, 1)) return(false);
                packetlen += b;
                if(1/*b < 0xff*/) {page.m_lens.AddTail(packetlen); pagelen += packetlen; packetlen = 0;}
        }

        if(fFull)
        {
                page.SetSize(pagelen);
                if(S_OK != Read(page.GetData(), page.GetSize())) 
                        return(false);
        }
        else
        {
                Seek(GetPos()+pagelen);
                page.m_lens.RemoveAll();
        }

        return(true);
}

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