Method feedPacketToDecoders

plugins/e57/libE57Format/src/CompressedVectorReaderImpl.cpp:358–505

   }

   void CompressedVectorReaderImpl::feedPacketToDecoders( uint64_t currentPacketLogicalOffset )
   {
      // Get packet at currentPacketLogicalOffset into memory.
      auto dpkt = dataPacket( currentPacketLogicalOffset );

      // Double check that have a data packet.  Should have already determined this.
      if ( dpkt->header.packetType != DATA_PACKET )
      {
         throw E57_EXCEPTION2( ErrorInternal, "packetType=" + toString( dpkt->header.packetType ) );
      }

      // Read earliest packet into cache and send data to decoders with unblocked output

      bool anyChannelHasExhaustedPacket = false;
      uint64_t nextPacketLogicalOffset = UINT64_MAX;

      // Feed bytestreams to channels with unblocked output that are reading from this packet
      for ( DecodeChannel &channel : channels_ )
      {
         // Skip channels that have already read this packet.
         if ( _alreadyReadPacket( channel, currentPacketLogicalOffset ) )
         {
            continue;
         }

         // Get bytestream buffer for this channel from packet
         unsigned int bsbLength = 0;
         const char *bsbStart = dpkt->getBytestream( channel.bytestreamNumber, bsbLength );

         // Double check we are not off end of buffer
         if ( channel.currentBytestreamBufferIndex > bsbLength )
         {
            throw E57_EXCEPTION2(
               ErrorInternal,
               "currentBytestreamBufferIndex =" + toString( channel.currentBytestreamBufferIndex ) +
                  " bsbLength=" + toString( bsbLength ) );
         }

         // Calc where we are in the buffer
         const char *uneatenStart = &bsbStart[channel.currentBytestreamBufferIndex];
         const size_t uneatenLength = bsbLength - channel.currentBytestreamBufferIndex;

         if ( &uneatenStart[uneatenLength] > &bsbStart[bsbLength] )
         {
            throw E57_EXCEPTION2( ErrorInternal, "uneatenLength=" + toString( uneatenLength ) +
                                                    " bsbLength=" + toString( bsbLength ) );
         }

         // Feed into decoder
         const size_t bytesProcessed = channel.decoder->inputProcess( uneatenStart, uneatenLength );

#ifdef E57_VERBOSE
         std::cout << "  stream[" << channel.bytestreamNumber << "]: feeding decoder "
                   << uneatenLength << " bytes" << std::endl;

         if ( uneatenLength == 0 )
         {
            channel.dump( 8 );