HTTPStreamingFileSource.h

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//===========================================================================
//Copyright (C) 2003-2006 Zentaro Kavanagh
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions
//are met:
//
//- Redistributions of source code must retain the above copyright
//  notice, this list of conditions and the following disclaimer.
//
//- Redistributions in binary form must reproduce the above copyright
//  notice, this list of conditions and the following disclaimer in the
//  documentation and/or other materials provided with the distribution.
//
//- Neither the name of Zentaro Kavanagh nor the names of contributors 
//  may be used to endorse or promote products derived from this software 
//  without specific prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
//``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
//LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
//PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE ORGANISATION OR
//CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
//EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
//PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
//PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
//LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
//NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
//SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//===========================================================================
#pragma once
#include "oggdllstuff.h"

#include "HTTPSocket.h"
#include "IFilterDataSource.h"
#include <string>
#include <sstream>
#include <fstream>

using namespace std;

class OGG_DEMUX2_API HTTPStreamingFileSource
        :       public IFilterDataSource
        ,       public CAMThread
        ,       protected HTTPSocket    
{
public:
        HTTPStreamingFileSource(void);
        virtual ~HTTPStreamingFileSource(void);

        //Consts
        static const unsigned long MEMORY_BUFFER_SIZE = 1024 * 1024 * 2;        //2 megs
        static const unsigned long MEMORY_BUFFER_LOW_TIDE = 1024 * 512 * 3; //1.5 megs
        //Thread commands
        static const int THREAD_RUN = 0;
        static const int THREAD_EXIT = 1;

        //IFilterDataSource Interface
        virtual unsigned long seek(unsigned long inPos);
        virtual void close() ;
        virtual bool open(string inSourceLocation, unsigned long inStartByte = 0);
        virtual void clear();
        virtual bool isEOF();
        virtual bool isError();
        virtual unsigned long read(char* outBuffer, unsigned long inNumBytes);
        virtual string shouldRetryAt();

        
        //CAMThread pure virtuals
        DWORD ThreadProc();



protected:
        void unChunk(unsigned char* inBuff, unsigned long inNumBytes);
        unsigned short getHTTPResponseCode(string inHTTPResponse);
        bool startThread();
        void DataProcessLoop();

        //SingleMediaFileCache mFileCache;
        CircularBuffer* mMemoryBuffer;

        bool mIsChunked;
        unsigned long mChunkRemains;

        bool mIsBufferFilling;

        bool mIsFirstChunk;
        string mRetryAt;

        fstream debugLog;
        fstream fileDump;
        fstream rawDump;

        unsigned char* mInterBuff;
        unsigned long mNumLeftovers;
        static  const unsigned long RECV_BUFF_SIZE = 1024;
        static const unsigned long STREAM_START_BUFFER_SIZE = 32 * 1024;

        //Fix for seekback on headers - since we only maintain a forward buffer. The seek back to start which occurs
        //      right after the headers are processed, will generally trigger a stream reset. But an annodex server,
        //      will serve out a file with completely different serial numbers, making it impossible to map the streams
        //      using the originally gathered information.
        //
        //Now we are going to buffer up the first part of the file into yet another buffer. Also keep track
        //      of what the absolute byte position is we have read up to so far from the stream. When we receive a seek request,
        //      we check if the current read position is within this new buffer.
        //
        //If it is, then we can set a flag, and respond to read requests from this new buffer, up until the point
        //      where the stream was before the seek, then switch back to serving out live streaming data.
        unsigned long mCurrentAbsoluteReadPosition;
        bool mFirstPass;

        unsigned char* mStreamStartBuffer;
        unsigned long mStreamStartBufferLength;

        unsigned long mApparentReadPosition;
        
        //

        __int64 mContentLength;

        CCritSec* mBufferLock;
};

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