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/* -*- c++ -*- */
/*
* Copyright 2004,2009,2013 Free Software Foundation, Inc.
* Copyright 2021 Marcus Müller
*
* This file is part of GNU Radio
*
* SPDX-License-Identifier: GPL-3.0-or-later
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "head_impl.h"
#include <gnuradio/io_signature.h>
#include <cstring>
namespace gr {
namespace blocks {
head::sptr head::make(size_t sizeof_stream_item, uint64_t nitems)
{
return gnuradio::make_block_sptr<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(0, 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;
// can have zero or one output port, if zero, don't copy
if (!output_items.empty()) {
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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