source_reader.hh

/*
 * Copyright (C) 2019  SUSE Software Solutions Germany GmbH
 *
 * This file is part of klp-ccp.
 *
 * klp-ccp is free software: you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * klp-ccp 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 klp-ccp. If not, see <https://www.gnu.org/licenses/>.
 */

#ifndef SOURCE_READER_HH
#define SOURCE_READER_HH

#include <vector>
#include <string>

namespace klp
{
  namespace ccp
  {
    class range_in_file;

    class source_reader
    {
    public:
      typedef std::vector<char> buffer_type;

      virtual ~source_reader() noexcept;

      virtual buffer_type read() = 0;

      virtual void read(buffer_type &to_buffer,
			const range_in_file &from_range) = 0;
    };

    class file_source_reader final : public source_reader
    {
    public:
      file_source_reader(const std::string &filename);

      virtual ~file_source_reader() noexcept override;

      virtual buffer_type read() override;

      virtual void read(buffer_type &to_buffer,
			const range_in_file &from_range) override;

    private:
      void _fill_buffer();

      const std::string _filename;
      int _fd;
      buffer_type _buf;
      std::streamoff _buf_pos;
    };
  }
}

#endif