diff options
Diffstat (limited to 'gr-blocks/lib/repack_bits_bb_impl.cc')
| -rw-r--r-- | gr-blocks/lib/repack_bits_bb_impl.cc | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/gr-blocks/lib/repack_bits_bb_impl.cc b/gr-blocks/lib/repack_bits_bb_impl.cc new file mode 100644 index 0000000000..c7ed054c8a --- /dev/null +++ b/gr-blocks/lib/repack_bits_bb_impl.cc @@ -0,0 +1,123 @@ +/* -*- c++ -*- */ +/* + * Copyright 2012 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. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <gr_io_signature.h> +#include "repack_bits_bb_impl.h" + +namespace gr { + namespace blocks { + + repack_bits_bb::sptr + repack_bits_bb::make(int k, int l, const std::string &len_tag_key, bool align_output) + { + return gnuradio::get_initial_sptr (new repack_bits_bb_impl(k, l, len_tag_key, align_output)); + } + + repack_bits_bb_impl::repack_bits_bb_impl(int k, int l, const std::string &len_tag_key, bool align_output) + : gr_tagged_stream_block("repack_bits_bb", + gr_make_io_signature(1, 1, sizeof (char)), + gr_make_io_signature(1, 1, sizeof (char)), + len_tag_key), + d_k(k), d_l(l), + d_packet_mode(!len_tag_key.empty()), + d_in_index(0), d_out_index(0), + d_align_output(align_output) + { + if (d_k > 8 || d_k < 1 || d_l > 8 || d_l < 1) { + throw std::invalid_argument("k and l must be in [1, 8]"); + } + + set_relative_rate((double) d_k / d_l); + } + + repack_bits_bb_impl::~repack_bits_bb_impl() + { + } + + int + repack_bits_bb_impl::calculate_output_stream_length(const gr_vector_int &ninput_items) + { + int n_out_bytes_required = (ninput_items[0] * d_k) / d_l; + if ((ninput_items[0] * d_k) % d_l && (!d_packet_mode || (d_packet_mode && !d_align_output))) { + n_out_bytes_required++; + } + + return n_out_bytes_required; + } + + int + repack_bits_bb_impl::work (int noutput_items, + gr_vector_int &ninput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) + { + const unsigned char *in = (const unsigned char *) input_items[0]; + unsigned char *out = (unsigned char *) output_items[0]; + int bytes_to_write = noutput_items; + + if (d_packet_mode) { // noutput_items could be larger than necessary + int bytes_to_read = ninput_items[0]; + bytes_to_write = bytes_to_read * d_k / d_l; + if (!d_align_output && (((bytes_to_read * d_k) % d_l) != 0)) { + bytes_to_write++; + } + } + + int n_read = 0; + int n_written = 0; + while(n_written < bytes_to_write && n_read < ninput_items[0]) { + if (d_out_index == 0) { // Starting a fresh byte + out[n_written] = 0; + } + out[n_written] |= ((in[n_read] >> d_in_index) & 0x01) << d_out_index; + + d_in_index = (d_in_index + 1) % d_k; + d_out_index = (d_out_index + 1) % d_l; + if (d_in_index == 0) { + n_read++; + d_in_index = 0; + } + if (d_out_index == 0) { + n_written++; + d_out_index = 0; + } + } + + if (d_packet_mode) { + if (d_out_index) { + n_written++; + d_out_index = 0; + } + } else { + consume_each(n_read); + } + + return n_written; + } + + } /* namespace blocks */ +} /* namespace gr */ + |