FileSignature.h

Go to the documentation of this file.

/*
    Copyright (C) 2006-2010, Hammersmith Imanet Ltd
    Copyright (C) 2013, University College London
    This file is part of STIR.
    SPDX-License-Identifier: Apache-2.0
 
    See STIR/LICENSE.txt for details
*/
#ifndef __stir_IO_FileSignature_h__
#define __stir_IO_FileSignature_h__
#include "stir/utilities.h"
#include <fstream>
#include <string>
#include <algorithm>
 
START_NAMESPACE_STIR


class FileSignature
{
public:

  explicit FileSignature(std::istream& input) { this->_read_signature(input); }
  explicit FileSignature(const std::string& filename)
  {
    std::ifstream input;
    open_read_binary(input, filename);
    this->_read_signature(input);
  }


  const char* get_signature() const { return this->_signature; }

  std::size_t size() const { return this->_size; }
 
private:
  static const std::size_t _max_signature_size = 1024U;
  char _signature[_max_signature_size];
  std::size_t _size;
 
  void _read_signature(std::istream& input)
  {
    // first initialise to zero, just in case the whole buffer isn't set
    std::fill(this->_signature, this->_signature + this->_max_signature_size, '\0');
    input.read(this->_signature, this->_max_signature_size);
    this->_signature[this->_max_signature_size - 1] = '\0';
    this->_size = static_cast<std::size_t>(input.gcount());
  }
};
 
END_NAMESPACE_STIR
#endif