OggPacketiser.cpp

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//===========================================================================
//Copyright (C) 2003, 2004 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.
//===========================================================================
#include "stdafx.h"
#include <libOOOgg/OggPacketiser.h>

OggPacketiser::OggPacketiser(void) 
        :       mPacketSink(NULL)
        ,       mPendingPacket(NULL)
        ,       mPacketiserState(PKRSTATE_OK)
        ,       mLooseMode(true)                                                //FIX::: This affects the validator.
        ,       mNumIgnorePackets(0)
        //,     mPrevGranPos(0)
        //,     mCurrentGranPos(0)
{
        //debugLog.open("g:\\logs\\packetise.log", ios_base::out);

}
OggPacketiser::OggPacketiser(IStampedOggPacketSink* inPacketSink)
        :       mPacketSink(inPacketSink)
        ,       mPendingPacket(NULL)
        ,       mPacketiserState(PKRSTATE_OK)
        ,       mLooseMode(true)                                                //FIX::: This affects the validator.
        ,       mNumIgnorePackets(0)
        //,     mPrevGranPos(0)
        //,     mCurrentGranPos(0)
{
        //debugLog.open("g:\\logs\\packetise.log", ios_base::out);
}

OggPacketiser::~OggPacketiser(void)
{
        //Don't delete the packet sink
        //debugLog.close();
}

IStampedOggPacketSink* OggPacketiser::packetSink() {
        return mPacketSink;
}
void OggPacketiser::setPacketSink(IStampedOggPacketSink* inPacketSink) {
        mPacketSink = inPacketSink;
}
bool OggPacketiser::reset() {
        //debugLog<<"Reset : "<<endl;
        delete mPendingPacket;
        mPendingPacket = NULL;
        mNumIgnorePackets = 0;
        mPacketiserState = PKRSTATE_OK;
        //mPrevGranPos = 0;
        //mCurrentGranPos = 0;
        return true;
}
bool OggPacketiser::acceptOggPage(OggPage* inOggPage) {                         //AOP::: Needs closer look
        //All callers to acceptOggPage give away their pointer
        // to this function. All functions implementing this interface
        // are responsible for deleting this page. All callers
        // should NULL their pointer immediately after calling
        // to avoid reusing them.
        // 

        //debugLog<<"acceptOggPage : Gran = "<<inOggPage->header()->GranulePos()<<"Num packs = "<<inOggPage->numPackets()<<endl;

        //If the page isn't a -1 page and it's got a different granpos save it.
        //if ( (inOggPage->header()->GranulePos() != -1) && (inOggPage->header()->GranulePos() != mCurrentGranPos)) {
        //      mPrevGranPos = mCurrentGranPos;

        //      //If the previous is higher than the
        //      if (mPrevGranPos > mCurrentGranPos) {
        //              mPrevGranPos = -1;
        //      }
        //      mCurrentGranPos = inOggPage->header()->GranulePos();
        //}

        //If the page header says its a continuation page...
        if ((inOggPage->header()->HeaderFlags() & 1) == 1) {
                //debugLog<<"acceptOggPage : Page says cont..."<<endl;
                
                if (inOggPage->numPackets() > 0) {
                        //debugLog<<"acceptOggPage : ...and there is at least 1 packet..."<<endl;
                
                        //... and we were expecting a continuation...
                        if (mPacketiserState == PKRSTATE_AWAITING_CONTINUATION) {
                                //debugLog<<"acceptOggPage : ... and we were waiting for a cont..."<<endl;

                                //... and the first packet is marked as a continuation...
                                if (inOggPage->getStampedPacket(0)->isContinuation()) {
                                        //debugLog<<"acceptOggPage : ... and the first packet is a cont..."<<endl;

                                        //... merge this packet into our pending page.
                                        //ASSERT when mPacketiserState = PKRSTATE_AWAITING_CONTINUATION, mPending page != NULL
                                        mPendingPacket->merge(inOggPage->getStampedPacket(0));
                                        
                                        //If even after merging this packet is still truncated...
                                        if (mPendingPacket->isTruncated()) {
                                                //debugLog<<"acceptOggPage : ... but the pending packet is still truncated..."<<endl;
                                                //Packet still not full. special case full page.
                                                //===
                                                // The only way the the pending packet can be truncated is if
                                                //  the first packet in the page is truncated, and the first
                                                //  packet in a page can only be truncated if it's also the 
                                                //  only packet on the page.
                                                //Considering it is incomplete ending a page the granule pos
                                                // will be -1.
                                                //This is a special type of page :
                                                // 1 incomlpete packet on the page
                                                // Continuation flag set
                                                // No complete packets end on this page
                                                // Granule pos is -1

                                                //debugLog<<"acceptOggPage : Go to cont state."<<endl;
                                                //We are still waiting for another continuation...
                                                mPacketiserState = PKRSTATE_AWAITING_CONTINUATION;              //This should be redundant, we should already be in this state.
                                                //First packet on page is now merged into pending packet.
                                        } else {
                                                //debugLog<<"acceptOggPage : ... now we can deliver it..."<<endl;
                                                //... the pending packet is now complete.
                                                
                                                //TODO::: Static alternative here ?
                                                
                                                //Deliver the packet to the packet sink...
                                                if (dispatchStampedOggPacket(mPendingPacket) == false) {
                                                        //debugLog<<"acceptOggPage : DELIVERY FAILED !"<<endl;
                                                        mPacketiserState = PKRSTATE_OK;
                                                        mPendingPacket = NULL;
                                                        delete inOggPage;
                                                        return false;
                                                }
                                                //debugLog<<"acceptOggPage : ... delivery sucessful..."<<endl;
                                                //debugLog<<"acceptOggPage : Back to OK State..."<<endl;
                                                //Go back to OK state
                                                mPacketiserState = PKRSTATE_OK;
                                                mPendingPacket = NULL;
                                                //First packet on page is merged and delivered.
                                        }
                                        //debugLog<<"acceptOggPage : Send all the other packets besides first and last..."<<endl;
                                        //Send every packet except the first and last to the packet sink.
                                        processPage(inOggPage, false, false);
                                } else {
                                        //debugLog<<"acceptOggPage : INTERNAL ERROR - Header says cont but packet doesn't."<<endl;
                                        //Header flag says continuation but first packet is not continued.
                                        mPacketiserState = PKRSTATE_INVALID_STREAM;
                                        
                                        delete inOggPage;
                                        throw 0;
                                }
                        } else {
                                //debugLog<<"acceptOggPage : UNEXPECTED CONT !"<<endl;
                                if (mLooseMode == true) {
                                        //debugLog<<"acceptOggPage : ... but we are ignoring it !"<<endl;
                                        //Just ignore when we get continuation pages, just drop the broken bit of packet.

                                        mPendingPacket = NULL;   //MEMCHECK::: Did i just leak memory ?
                                        mPacketiserState = PKRSTATE_OK;

                                        //TODO::: Should really return false here if this returns false.
                                        if( processPage(inOggPage, false, false) == false) {
                                                //TODO::: State change ???
                                                delete inOggPage;
                                                return false;
                                        }
                                } else {
                                        //debugLog<<"acceptOggPage : FAILURE !!!!"<<endl;
                                        //Unexpected continuation
                                        mPacketiserState = PKRSTATE_INVALID_STREAM;
                                        throw 0;
                                }
                        }
                } else {
                        //debugLog<<"acceptOggPage : UNKNOWN CASE"<<endl;
                        //Is this something ?
                        //UNKNOWN CASE::: Header continuation flag set, but no packets on page.
                        mPacketiserState = PKRSTATE_INVALID_STREAM;
                        delete inOggPage;
                        throw 0;
                }
        } else {
                //debugLog<<"acceptOggPage : We have a normal page... dumping all but the last..."<<endl;
                //Normal page, no continuations... just dump the packets, except the last one
                if (inOggPage->numPackets() == 1) {

                        //I think the bug is here... by sending a trunc packet and not updating state.

                        //debugLog<<"acceptOggPage : Only one packet on this normal page..."<<endl;

                        if (inOggPage->getPacket(0)->isTruncated()) {
                                //debugLog<<"acceptOggPage : ...and it's truncated... so we save it."<<endl;
                                //ASSERT : mPending packet is NULL, because this is not a continuation page.
                                mPendingPacket = (StampedOggPacket*)inOggPage->getStampedPacket(0)->clone();
                                //debugLog<<"acceptOggPage : Moving to CONT state."<<endl;
                                mPacketiserState = PKRSTATE_AWAITING_CONTINUATION;

                        } else {
                                //debugLog<<"acceptOggPage : Only one packet on this normal page..."<<endl;
                                if (processPage(inOggPage, true, true) == false ) {                     //If there was only one pack process it.
                                        //debugLog<<"acceptOggPage : FAIL STATE DELIVERY"<<endl;
                                        //TODO::: State change
                                        delete inOggPage;
                                        return false;
                                }

                                //We should never go into the if below now as the packet is taken care of.
                        }
                } else {
                        //debugLog<<"acceptOggPage : More than one packet so dumping all but last..."<<endl;
                        if (processPage(inOggPage, true, false) == false ) {                    //If there was only one packet, no packets would be written
                                //debugLog<<"acceptOggPage : FAIL STATE DELIVERY"<<endl;
                                //TODO::: State change
                                delete inOggPage;
                                return false;                   
                        }
                }
                
                //The first packet is delivered.
        }

        //debugLog<<"acceptOggPage : First pack should be delivered..."<<endl;
        //ASSERT: By this point something has been done with the first packet.

        // It was either merged with pending page and possibly delivered
        // or it was delivered by process page.
        //Code following assumes the first packet is dealt with already.
        
        //Now we deal with the last packet...
        //ASSERT : The last packet has only been sent if there was 1 or less packets.

        //If there is at least two packet on the page... ie at least one more packet we haven't processed.
        if (inOggPage->numPackets() > 1) {
                //debugLog<<"acceptOggPage : There is at least one packet on the page we haven't processed"<<endl;
                //... and we are in the OK state
                if (mPacketiserState == PKRSTATE_OK) {
                        //debugLog<<"acceptOggPage : ... and we are in the OK state..."<<endl;
                        //If the last packet is truncated.
                        if (inOggPage->getPacket(inOggPage->numPackets() - 1)->isTruncated()) {
                                //debugLog<<"acceptOggPage : ... but the last packet is trunced... so we save it and wait for cont..."<<endl;
                                //The last packet is truncated. Save it and await continuation.
                                
                                //debugLog<<"acceptOggPage : Moving to CONT state..."<<endl;
                                mPacketiserState = PKRSTATE_AWAITING_CONTINUATION;
                        
                                //ASSERT when mPacketiserState = OK, mPendingPacket = NULL
                                mPendingPacket = (StampedOggPacket*)(inOggPage->getStampedPacket(inOggPage->numPackets() - 1)->clone());
                                //This packet is not delivered, it waits for a continuation.
                        } else {
                                //We are in the OK state, with no pending packets, and the last packet is not truncated.
                                //debugLog<<"acceptOggPage : The last page is not trunc so we send it..."<<endl;
                                //Deliver to the packet sink.
                                if ( dispatchStampedOggPacket( (StampedOggPacket*)(inOggPage->getStampedPacket(inOggPage->numPackets() - 1)->clone()) ) == false ) {
                                        //debugLog<<"acceptOggPage : Delivery failed..."<<endl;
                                        //TODO::: State change ?
                                        delete inOggPage;
                                        return false;
                                }
                                //The last packet is complete. So send it.
                        }
                } else if (mPacketiserState == PKRSTATE_AWAITING_CONTINUATION) {
                        //FIX::: This case should never occur.
                        //debugLog<<"acceptOggPage : NEVER BE HERE 1"<<endl;
                        
                        //Packetiser state is not ok... what to do abo8ut it.
                        
                        //See special page case above.
                        //This can only happen when we went through the special case above, and kept
                        // the state in  the continuation state. But by definition it is impossible
                        // for a subsequent packet on this page to be a continuation packet
                        // as continuation packets can only be the first packet on the page.
                        //This is more likely to be due to inconsistency of state code than invalidaity
                        // of file.
                        mPacketiserState = PKRSTATE_INVALID_STREAM;
                        delete inOggPage;
                        throw 0;
                } else {
                        //debugLog<<"acceptOggPage : NEVER BE HERE 2"<<endl;
                        //Shouldn't be here
                        mPacketiserState = PKRSTATE_INVALID_STREAM;
                        delete inOggPage;
                        throw 0;
                }
        } else {
                //debugLog<<"acceptOggPage : 1 packet on page only, and we've taken care of it."<<endl;
                //Zero packets on page.
        }
        //debugLog<<"acceptOggPage : All ok... returning..."<<endl<<endl;
        delete inOggPage;
        return true;
}

bool OggPacketiser::processPage(OggPage* inOggPage, bool inIncludeFirst, bool inIncludeLast) {
        //Returns false only if one of the acceptStampedOggPacket calls return false... means we should stop sending stuff and return.
        bool locIsOK = true;
        //debugLog<<"processPage : "<<endl;
        //Adjusts the loop parameters so that only packets excluding those specified are written.
        for (   int i = ((inIncludeFirst) ? 0 : 1); 
                        i < ((int)inOggPage->numPackets()) - ((inIncludeLast) ? 0 : 1);
                        i++) 
        {
                                //debugLog<<"processPage : Packet "<< i <<endl;         
                                locIsOK = (locIsOK && dispatchStampedOggPacket((StampedOggPacket*)inOggPage->getStampedPacket(i)->clone()));    //Gives away new packet.
                                if (!locIsOK) {
                                        //debugLog<<"processPage : FAIL STATE"<<endl;
                                        //TODO::: State change ???
                                        return false;
                                }
        }
        //debugLog<<"processPage : returning..."<<endl;
        return true;

}

bool OggPacketiser::dispatchStampedOggPacket(StampedOggPacket* inPacket) {      //Accepts packet... and gives it away or deletes it.
        if (mNumIgnorePackets > 0) {
                //Ignore this packet.
                mNumIgnorePackets--;

                //MEMCHECK::: Should probably delete this packet here.]
                delete inPacket;
                return true;
        } else {
                //Modify the header packet to include the gran pos of previous page.
                //if (mPrevGranPos != -1) {
                //      inPacket->setTimeStamp(mPrevGranPos, mCurrentGranPos, StampedOggPacket::OGG_BOTH);
                //}
                //Dispatch it.
                return mPacketSink->acceptStampedOggPacket(inPacket);
        }
}

void OggPacketiser::setNumIgnorePackets(unsigned long inNumIgnorePackets) {
        mNumIgnorePackets = inNumIgnorePackets;
}
unsigned long OggPacketiser::numIgnorePackets() {
        return mNumIgnorePackets;
}

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