GNU Radio 3.5.1 C++ API
gr_head.h
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00001 /* -*- c++ -*- */
00002 /*
00003  * Copyright 2004,2009 Free Software Foundation, Inc.
00004  * 
00005  * This file is part of GNU Radio
00006  * 
00007  * GNU Radio is free software; you can redistribute it and/or modify
00008  * it under the terms of the GNU General Public License as published by
00009  * the Free Software Foundation; either version 3, or (at your option)
00010  * any later version.
00011  * 
00012  * GNU Radio is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015  * GNU General Public License for more details.
00016  * 
00017  * You should have received a copy of the GNU General Public License
00018  * along with GNU Radio; see the file COPYING.  If not, write to
00019  * the Free Software Foundation, Inc., 51 Franklin Street,
00020  * Boston, MA 02110-1301, USA.
00021  */
00022 
00023 #ifndef INCLUDED_GR_HEAD_H
00024 #define INCLUDED_GR_HEAD_H
00025 
00026 #include <gr_core_api.h>
00027 #include <gr_sync_block.h>
00028 #include <stddef.h>                     // size_t
00029 
00030 class gr_head;
00031 typedef boost::shared_ptr<gr_head> gr_head_sptr;
00032 
00033 /*!
00034  * \brief copies the first N items to the output then signals done
00035  * \ingroup slicedice_blk
00036  *
00037  * Useful for building test cases
00038  */
00039 
00040 class GR_CORE_API gr_head : public gr_sync_block
00041 {
00042   friend GR_CORE_API gr_head_sptr gr_make_head (size_t sizeof_stream_item, unsigned long long nitems);
00043   gr_head (size_t sizeof_stream_item, unsigned long long nitems);
00044 
00045   unsigned long long    d_nitems;
00046   unsigned long long    d_ncopied_items;
00047 
00048  public:
00049   int work (int noutput_items,
00050                  gr_vector_const_void_star &input_items,
00051                  gr_vector_void_star &output_items);
00052 
00053   void reset() { d_ncopied_items = 0; }
00054 };
00055 
00056 GR_CORE_API gr_head_sptr
00057 gr_make_head (size_t sizeof_stream_item, unsigned long long nitems);
00058 
00059 
00060 #endif /* INCLUDED_GR_HEAD_H */