Disk ARchive  2.4.2
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups
elastic.hpp
Go to the documentation of this file.
1 /*********************************************************************/
2 // dar - disk archive - a backup/restoration program
3 // Copyright (C) 2002-2052 Denis Corbin
4 //
5 // This program is free software; you can redistribute it and/or
6 // modify it under the terms of the GNU General Public License
7 // as published by the Free Software Foundation; either version 2
8 // of the License, or (at your option) any later version.
9 //
10 // This program is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 // GNU General Public License for more details.
14 //
15 // You should have received a copy of the GNU General Public License
16 // along with this program; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 //
19 // to contact the author : http://dar.linux.free.fr/email.html
20 /*********************************************************************/
21 // $Id: elastic.hpp,v 1.9 2011/01/09 17:25:58 edrusb Rel $
22 //
23 /*********************************************************************/
24 
28 
29 #ifndef ELASTIC_HPP
30 #define ELASTIC_HPP
31 
32 #include "../my_config.h"
33 
34 #include "integers.hpp"
35 #include "erreurs.hpp"
36 #include "infinint.hpp"
37 #include "generic_file.hpp"
38 #include "header_version.hpp"
39 
40 
41 namespace libdar
42 {
43 
46 
47 
48  enum elastic_direction { elastic_forward, elastic_backward };
49 
51 
56  class elastic
57  {
58  public:
59  elastic(U_32 size);
60  elastic(const unsigned char *buffer, U_32 size, elastic_direction dir, const archive_version & reading_ver);
61  elastic(generic_file &f, elastic_direction dir, const archive_version & reading_ver);
62 
63  U_32 dump(unsigned char *buffer, U_32 size) const;
64  U_32 get_size() const { return taille; };
65 
66  static U_I max_length() { return (U_I)(254)*254*254*254 - 1; };
67 
68  private:
69  U_32 taille; // max size of elastic buffer is 4GB which is large enough
70 
71  void randomize(unsigned char *a) const;
72  U_I base_from_version(const archive_version & reading_ver) const;
73  unsigned char get_low_mark(const archive_version & reading_ver) const;
74  unsigned char get_high_mark(const archive_version & reading_ver) const;
75  unsigned char get_low_mark() const { return 255; };
76  unsigned char get_high_mark() const { return 254; };
77 
78  };
79 
81 
82 } // end of namespace
83 
84 #endif