gr_sync_block.cc

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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 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_sync_block.h>

gr_sync_block::gr_sync_block (const std::string &name,
			      gr_io_signature_sptr input_signature,
			      gr_io_signature_sptr output_signature)
  : gr_block(name, input_signature, output_signature)
{
  set_fixed_rate(true);
}


void
gr_sync_block::forecast (int noutput_items, gr_vector_int &ninput_items_required)
{
  unsigned ninputs = ninput_items_required.size();
  for (unsigned i = 0; i < ninputs; i++)
    ninput_items_required[i] = fixed_rate_noutput_to_ninput (noutput_items);
}

int
gr_sync_block::fixed_rate_noutput_to_ninput(int noutput_items)
{
  return noutput_items + history() - 1;
}

int
gr_sync_block::fixed_rate_ninput_to_noutput(int ninput_items)
{
  return std::max(0, ninput_items - (int)history() + 1);
}

int
gr_sync_block::general_work (int noutput_items,
			     gr_vector_int &ninput_items,
			     gr_vector_const_void_star &input_items,
			     gr_vector_void_star &output_items)
{
  int	r = work (noutput_items, input_items, output_items);
  if (r > 0)
    consume_each (r);
  return r;
}