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/* -*- c++ -*- */
/*
* Copyright 2004,2009,2013 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 "head_impl.h"
#include <gnuradio/io_signature.h>
#include <string.h>
namespace gr {
namespace blocks {
head::sptr
head::make(size_t sizeof_stream_item, uint64_t nitems)
{
return gnuradio::get_initial_sptr
(new head_impl(sizeof_stream_item, nitems));
}
head_impl::head_impl(size_t sizeof_stream_item, uint64_t nitems)
: sync_block("head",
io_signature::make(1, 1, sizeof_stream_item),
io_signature::make(1, 1, sizeof_stream_item)),
d_nitems(nitems), d_ncopied_items(0)
{
}
head_impl::~head_impl()
{
}
int
head_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
if(d_ncopied_items >= d_nitems)
return -1; // Done!
unsigned n = std::min(d_nitems - d_ncopied_items,
(uint64_t)noutput_items);
if(n == 0)
return 0;
memcpy(output_items[0], input_items[0],
n * input_signature()->sizeof_stream_item (0));
d_ncopied_items += n;
return n;
}
} /* namespace blocks */
} /* namespace gr */
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