csvorbis.Mapping0.unpack C# (CSharp) Method

        public override Object unpack(Info vi, csBuffer opb)
        {
            // also responsible for range checking
            InfoMapping0 info=new InfoMapping0();

            // !!!!
            if(opb.read(1)!=0)
            {
                info.submaps=opb.read(4)+1;
            }
            else
            {
                info.submaps=1;
            }

            if(opb.read(1)!=0)
            {
                info.coupling_steps=opb.read(8)+1;

                for(int i=0;i<info.coupling_steps;i++)
                {
                    int testM=info.coupling_mag[i]=opb.read(ilog2(vi.channels));
                    int testA=info.coupling_ang[i]=opb.read(ilog2(vi.channels));

                    if(testM<0 ||
                        testA<0 ||
                        testM==testA ||
                        testM>=vi.channels ||
                        testA>=vi.channels)
                    {
                        //goto err_out;
                        info.free();
                        return(null);
                    }
                }
            }

            if(opb.read(2)>0)
            { /* 2,3:reserved */
                //goto err_out;
                info.free();
                return(null);
            }

            if(info.submaps>1)
            {
                for(int i=0;i<vi.channels;i++)
                {
                    info.chmuxlist[i]=opb.read(4);
                    if(info.chmuxlist[i]>=info.submaps)
                    {
                        //goto err_out;
                        info.free();
                        return(null);
                    }
                }
            }

            for(int i=0;i<info.submaps;i++)
            {
                info.timesubmap[i]=opb.read(8);
                if(info.timesubmap[i]>=vi.times)
                {
                    //goto err_out;
                    info.free();
                    return(null);
                }
                info.floorsubmap[i]=opb.read(8);
                if(info.floorsubmap[i]>=vi.floors)
                {
                    //goto err_out;
                    info.free();
                    return(null);
                }
                info.residuesubmap[i]=opb.read(8);
                if(info.residuesubmap[i]>=vi.residues)
                {
                    //goto err_out;
                    info.free();
                    return(null);
                }
            }
            return info;
            //err_out:
            //free_info(info);
            //return(NULL);
        }