diff options
| author | Tom Rondeau <trondeau@vt.edu> | 2013-03-17 11:43:10 -0400 |
|---|---|---|
| committer | Tom Rondeau <trondeau@vt.edu> | 2013-03-17 11:43:10 -0400 |
| commit | ee2b700f72503d6e7f62adbfb7dff9997b9cb003 (patch) | |
| tree | 2c7e91d03fb5c605c6deebac9077c1bc41bce13d /gr-blocks/lib/skiphead_impl.cc | |
| parent | f15400470ce5cb68f5339ead7af726b8bbafd364 (diff) | |
| parent | 65d88f0b28e233c82bc4f0c07072085a3d18c163 (diff) | |
Merge branch 'master' into next
Conflicts:
gr-blocks/swig/blocks_swig.i
Diffstat (limited to 'gr-blocks/lib/skiphead_impl.cc')
| -rw-r--r-- | gr-blocks/lib/skiphead_impl.cc | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/gr-blocks/lib/skiphead_impl.cc b/gr-blocks/lib/skiphead_impl.cc new file mode 100644 index 0000000000..feb39eb8f4 --- /dev/null +++ b/gr-blocks/lib/skiphead_impl.cc @@ -0,0 +1,93 @@ +/* -*- c++ -*- */ +/* + * Copyright 2005,2007,2010,2013 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 "skiphead_impl.h" +#include <gr_io_signature.h> +#include <string.h> + +namespace gr { + namespace blocks { + + skiphead::sptr + skiphead::make(size_t itemsize, uint64_t nitems_to_skip) + { + return gnuradio::get_initial_sptr + (new skiphead_impl(itemsize, nitems_to_skip)); + } + + skiphead_impl::skiphead_impl(size_t itemsize, uint64_t nitems_to_skip) + : gr_block("skiphead", + gr_make_io_signature(1, 1, itemsize), + gr_make_io_signature(1, 1, itemsize)), + d_nitems_to_skip(nitems_to_skip), d_nitems(0) + { + } + + skiphead_impl::~skiphead_impl() + { + } + + int + skiphead_impl::general_work(int noutput_items, + gr_vector_int &ninput_items_, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) + { + const char *in = (const char*)input_items[0]; + char *out = (char*)output_items[0]; + + int ninput_items = std::min(ninput_items_[0], noutput_items); + int ii = 0; // input index + + while (ii < ninput_items) { + uint64_t ni_total = ii + d_nitems; // total items processed so far + if(ni_total < d_nitems_to_skip) { // need to skip some more + + int n_to_skip = (int)std::min(d_nitems_to_skip - ni_total, + (uint64_t)(ninput_items - ii)); + ii += n_to_skip; + } + + else { // nothing left to skip. copy away + int n_to_copy = ninput_items - ii; + if(n_to_copy > 0) { + size_t itemsize = output_signature()->sizeof_stream_item(0); + memcpy(out, in + (ii*itemsize), n_to_copy*itemsize); + } + + d_nitems += ninput_items; + consume_each(ninput_items); + return n_to_copy; + } + } + + d_nitems += ninput_items; + consume_each(ninput_items); + return 0; + } + + } /* namespace blocks */ +} /* namespace gr */ |