Disk ARchive  2.7.15
Full featured and portable backup and archiving tool
xz_module.hpp
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2 // dar - disk archive - a backup/restoration program
3 // Copyright (C) 2002-2024 Denis Corbin
4 //
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21 
26 
27 #ifndef XZ_MODULE_HPP
28 #define XZ_MODULE_HPP
29 
30 extern "C"
31 {
32 #if HAVE_LZMA_H
33 #include <lzma.h>
34 #endif
35 }
36 
37 #include "../my_config.h"
38 
39 #include "compress_module.hpp"
40 #include "infinint.hpp"
41 
42 namespace libdar
43 {
44 
47 
48  class xz_module: public compress_module
49  {
50  public:
51  xz_module(U_I compression_level = 9);
52  xz_module(const xz_module & ref) { setup(ref.level); };
53  xz_module(xz_module && ref) noexcept = default;
54  xz_module & operator = (const xz_module & ref) { end_process(); setup(ref.level); return *this; };
55  xz_module & operator = (xz_module && ref) noexcept = default;
56  virtual ~xz_module() { end_process(); };
57 
58  // inherited from compress_module interface
59 
60  virtual compression get_algo() const override { return compression::xz; };
61 
62  virtual U_I get_max_compressing_size() const override;
63 
64  virtual U_I get_min_size_to_compress(U_I clear_size) const override;
65 
66  virtual U_I compress_data(const char *normal,
67  const U_I normal_size,
68  char *zip_buf,
69  U_I zip_buf_size) const override;
70 
71  virtual U_I uncompress_data(const char *zip_buf,
72  const U_I zip_buf_size,
73  char *normal,
74  U_I normal_size) const override;
75 
76 
77  virtual std::unique_ptr<compress_module> clone() const override;
78 
79  private:
80  U_I level;
81 #if LIBLZMA_AVAILABLE
82  mutable lzma_stream lzma_str;
83 #endif
84 
85  void setup(U_I compression_level);
86  void init_decompr() const;
87  void init_compr() const;
88  void end_process() const;
89  };
90 
92 
93 } // end of namespace
94 
95 #endif
provides abstracted interface of per-block compression/decompression
compression
the different compression algorithm available
Definition: compression.hpp:46
@ xz
lzma compression (streamed)
switch module to limitint (32 ou 64 bits integers) or infinint
libdar namespace encapsulate all libdar symbols
Definition: archive.hpp:47