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/* -*- c++ -*- */
/*
* Copyright 2004 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 2, 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_head.h>
#include <gr_io_signature.h>
gr_head::gr_head (size_t sizeof_stream_item, int nitems)
: gr_sync_block ("head",
gr_make_io_signature (1, 1, sizeof_stream_item),
gr_make_io_signature (1, 1, sizeof_stream_item)),
d_nitems (nitems), d_ncopied_items (0)
{
}
gr_block_sptr
gr_make_head (size_t sizeof_stream_item, int nitems)
{
return gr_block_sptr (new gr_head (sizeof_stream_item, nitems));
}
int
gr_head::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, 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;
}
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