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/* -*- c++ -*- */
/*
* Copyright 2014 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef INCLUDED_FEC_ASYNC_ENCODER_H
#define INCLUDED_FEC_ASYNC_ENCODER_H
#include <gnuradio/fec/api.h>
#include <gnuradio/fec/generic_encoder.h>
#include <gnuradio/block.h>
#include <boost/shared_ptr.hpp>
namespace gr {
namespace fec {
/*!
* \brief Creates the encoder block for use in GNU Radio
* flowgraphs with async message from a given FEC API object
* derived from the generic_encoder class.
* \ingroup error_coding_blk
*
* \details
*
* Encodes frames received as async messages or as a PDU over a
* message port. This encoder works off a full message as one
* frame or block to encode. The message length is used as the
* frame length. To support this, the encoder variable used will
* have had its frame_size set. This block treats that initial
* frame_size value as the maximum transmission unit (MTU) and
* will not process frames larger than that.
*
* This deployment works off messages and expects them to either
* be messages full of unpacked bits or PDU messages, which means
* full bytes of a frame from the higher layers, including things
* like headers, tails, CRC check bytes, etc. For handling PDUs,
* set the \p packed option of this deployment block to True. The
* block will then use the FEC API to properly unpack the bits
* from the PDU, pass it through the encoder, and repack them to
* output the PDUs for the next stage of processing.
*
* The packed PDU form of this deployment is designed to work well
* with other PDU-based blocks to operate within the processing
* flow of data packets or frames.
*
* Due to differences in how data is packed and processed, this
* block also offers the ability to change the direction of how
* bits are unpacked and packed, where reading or writing from the
* LSB or MSB. By default, the \p rev_unpack and \p rev_pack modes
* are set to True. Using this setup allows the async block to
* behave with PDUs in the same operation and format as the tagged
* stream encoders. That is, putting the same data into both the
* tagged stream encoder deployment and this with these default
* settings should produce the same data.
*/
class FEC_API async_encoder : virtual public block
{
public:
typedef boost::shared_ptr<async_encoder> sptr;
/*!
* Build the PDU-based FEC encoder block from an FECAPI encoder object.
*
* \param my_encoder An FECAPI encoder object child of the generic_encoder class.
* \param packed True if working on packed bytes (like PDUs).
* \param rev_unpack Reverse the unpacking order from input bytes to bits.
* \param rev_pack Reverse the packing order from bits to output bytes.
* \param mtu The Maxium Transmission Unit (MTU) of the input
* frame that the block will be able to
* process. Specified in bytes and defaults to 1500.
*/
static sptr make(generic_encoder::sptr my_encoder,
bool packed=false,
bool rev_unpack=true, bool rev_pack=true,
int mtu=1500);
virtual int general_work(int noutput_items,
gr_vector_int& ninput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items) = 0;
};
} /* namespace fec */
} /* namespace gr */
#endif /* INCLUDED_FEC_ASYNC_ENCODER_H */
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