gr_file_source.h

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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.
 */

#ifndef INCLUDED_GR_FILE_SOURCE_H
#define INCLUDED_GR_FILE_SOURCE_H

#include <gr_core_api.h>
#include <gr_sync_block.h>
#include <boost/thread/mutex.hpp>

class gr_file_source;
typedef boost::shared_ptr<gr_file_source> gr_file_source_sptr;

GR_CORE_API gr_file_source_sptr
gr_make_file_source (size_t itemsize, const char *filename, bool repeat = false);

/*!
 * \brief Read stream from file
 * \ingroup source_blk
 */

class GR_CORE_API gr_file_source : public gr_sync_block
{
 private:
  size_t d_itemsize;
  FILE *d_fp;
  FILE *d_new_fp;
  bool d_repeat;
  bool d_updated;

 protected:
  gr_file_source(size_t itemsize, const char *filename, bool repeat);

  void do_update();

  boost::mutex fp_mutex;

 public:
  /*!
   * \brief Create a file source.
   *
   * Opens \p filename as a source of items into a flowgraph. The data
   * is expected to be in binary format, item after item. The \p
   * itemsize of the block determines the conversion from bits to
   * items.
   *
   * If \p repeat is turned on, the file will repeat the file after
   * it's reached the end.
   *
   * \param itemsize    the size of each item in the file, in bytes
   * \param filename    name of the file to source from
   * \param repeat      repeat file from start
   */
  friend GR_CORE_API gr_file_source_sptr
    gr_make_file_source(size_t itemsize,
                        const char *filename,
                        bool repeat);

  ~gr_file_source();

  int work(int noutput_items,
           gr_vector_const_void_star &input_items,
           gr_vector_void_star &output_items);

  /*!
   * \brief Seek file to \p seek_point relative to \p whence
   *
   * \param seek_point  sample offset in file
   * \param whence      one of SEEK_SET, SEEK_CUR, SEEK_END (man fseek)
   */
  bool seek(long seek_point, int whence);

  /*!
   * \brief Opens a new file.
   *
   * \param filename    name of the file to source from
   * \param repeat      repeat file from start
   */
  void open(const char *filename, bool repeat);

  /*!
   * \brief Close the file handle.
   */
  void close();

};

#endif /* INCLUDED_GR_FILE_SOURCE_H */