Disk ARchive  2.6.8
Full featured and portable backup and archiving tool
hash_fichier.hpp
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1 /*********************************************************************/
2 // dar - disk archive - a backup/restoration program
3 // Copyright (C) 2002-2020 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
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9 //
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21 
29 
30 #ifndef HASH_FICHIER_HPP
31 #define HASH_FICHIER_HPP
32 
33 #include "../my_config.h"
34 
35 extern "C"
36 {
37 #if HAVE_GCRYPT_H
38 #ifndef GCRYPT_NO_DEPRECATED
39 #define GCRYPT_NO_DEPRECATED
40 #endif
41 #include <gcrypt.h>
42 #endif
43 }
44 
45 #include <string>
46 
47 #include "fichier_global.hpp"
48 #include "integers.hpp"
49 #include "archive_aux.hpp"
50 
51 namespace libdar
52 {
53 
56 
58 
60  {
61  public:
62 
71 
72  hash_fichier(const std::shared_ptr<user_interaction> & dialog,
73  fichier_global *under,
74  const std::string & under_filename,
75  fichier_global *hash_file,
76  hash_algo algo);
77 
79  hash_fichier(const hash_fichier & ref) = delete;
80 
82  hash_fichier(hash_fichier && ref) noexcept = delete;
83 
85  hash_fichier & operator = (const hash_fichier & ref) = delete;
86 
88  hash_fichier & operator = (hash_fichier && ref) noexcept = delete;
89 
91  ~hash_fichier();
92 
93  // inherited from fichier_global
94  virtual void change_ownership(const std::string & user, const std::string & group) override { if(ref == nullptr || hash_ref == nullptr) throw SRC_BUG; ref->change_ownership(user, group); hash_ref->change_ownership(user, group); };
95  virtual void change_permission(U_I perm) override { if(ref == nullptr || hash_ref == nullptr) throw SRC_BUG; ref->change_permission(perm); hash_ref->change_permission(perm); };
96  virtual infinint get_size() const override { if(ref == nullptr) throw SRC_BUG; return ref->get_size(); };
97  virtual void fadvise(advise adv) const override { if(ref == nullptr) throw SRC_BUG; ref->fadvise(adv); };
98 
99  // inherited from generic_file
100  virtual bool skippable(skippability direction, const infinint & amount) override { return false; };
101  virtual bool skip(const infinint & pos) override {if(ref == nullptr || pos != ref->get_position()) throw SRC_BUG; else return true; };
102  virtual bool skip_to_eof() override { if(get_mode() == gf_write_only) return true; else throw SRC_BUG; };
103  virtual bool skip_relative(S_I x) override { if(x != 0) throw SRC_BUG; else return true; };
104  virtual infinint get_position() const override { if(ref == nullptr) throw SRC_BUG; return ref->get_position(); };
105 
107  void set_only_hash() { only_hash = true; };
108 
109  protected:
110  // inherited from fichier_global
111  virtual void inherited_read_ahead(const infinint & amount) override { ref->read_ahead(amount); };
112  virtual U_I fichier_global_inherited_write(const char *a, U_I size) override;
113  virtual bool fichier_global_inherited_read(char *a, U_I size, U_I & read, std::string & message) override;
114 
115  // inherited from generic_file
116  virtual void inherited_sync_write() override {};
117  virtual void inherited_flush_read() override {};
118  virtual void inherited_terminate() override;
119 
120  private:
121  fichier_global *ref;
122  fichier_global *hash_ref;
123  bool only_hash;
124 #if CRYPTO_AVAILABLE
125  gcry_md_hd_t hash_handle;
126 #endif
127  std::string ref_filename;
128  U_I hash_gcrypt;
129  bool eof;
130  bool hash_dumped;
131  };
132 
134 
135 } // end of namespace
136 
137 
138 #endif
libdar::hash_fichier::change_ownership
virtual void change_ownership(const std::string &user, const std::string &group) override
set the ownership of the file
Definition: hash_fichier.hpp:94
libdar::hash_algo
hash_algo
hashing algorithm available
Definition: archive_aux.hpp:62
libdar::hash_fichier::inherited_sync_write
virtual void inherited_sync_write() override
write down any pending data
Definition: hash_fichier.hpp:116
libdar::hash_fichier::~hash_fichier
~hash_fichier()
destructor
libdar::fichier_global::change_permission
virtual void change_permission(U_I perm)=0
change the permission of the file
libdar::hash_fichier::get_size
virtual infinint get_size() const override
return the size of the file
Definition: hash_fichier.hpp:96
integers.hpp
are defined here basic integer types that tend to be portable
libdar::hash_fichier::fichier_global_inherited_write
virtual U_I fichier_global_inherited_write(const char *a, U_I size) override
replaces generic_file::inherited_write() method, to allow the return of partial writings
libdar::hash_fichier::hash_fichier
hash_fichier(const std::shared_ptr< user_interaction > &dialog, fichier_global *under, const std::string &under_filename, fichier_global *hash_file, hash_algo algo)
libdar::infinint
the arbitrary large positive integer class
Definition: real_infinint.hpp:61
libdar::hash_fichier::set_only_hash
void set_only_hash()
for debugging purposes only
Definition: hash_fichier.hpp:107
libdar::hash_fichier
manages the generation of a hash
Definition: hash_fichier.hpp:59
libdar::hash_fichier::fadvise
virtual void fadvise(advise adv) const override
set posix_fadvise for the whole file
Definition: hash_fichier.hpp:97
libdar::hash_fichier::only_hash
bool only_hash
if set, avoids copying data to file, only compute hash (debugging purpose)
Definition: hash_fichier.hpp:123
libdar::hash_fichier::inherited_terminate
virtual void inherited_terminate() override
destructor-like call, except that it is allowed to throw exceptions
libdar::fichier_global::advise
advise
Definition: fichier_global.hpp:61
libdar::fichier_global::change_ownership
virtual void change_ownership(const std::string &user, const std::string &group)=0
set the ownership of the file
libdar::generic_file::get_mode
gf_mode get_mode() const
retreive the openning mode for this object
Definition: generic_file.hpp:109
fichier_global.hpp
class fichier_global definition. This class is a pure virtual class class fichier_global is an abstra...
libdar::hash_fichier::skippable
virtual bool skippable(skippability direction, const infinint &amount) override
whether the implementation is able to skip
Definition: hash_fichier.hpp:100
libdar::hash_fichier::operator=
hash_fichier & operator=(const hash_fichier &ref)=delete
assignment operator
libdar::hash_fichier::inherited_read_ahead
virtual void inherited_read_ahead(const infinint &amount) override
tells the object that several calls to read() will follow to probably obtain at least the given amoun...
Definition: hash_fichier.hpp:111
libdar::gf_write_only
write only access
Definition: gf_mode.hpp:46
libdar::hash_fichier::skip_to_eof
virtual bool skip_to_eof() override
skip to the end of file
Definition: hash_fichier.hpp:102
libdar::generic_file::read_ahead
void read_ahead(const infinint &amount)
archive_aux.hpp
set of datastructures used to interact with a catalogue object
libdar::hash_fichier::inherited_flush_read
virtual void inherited_flush_read() override
reset internal engine, flush caches in order to read the data at current position
Definition: hash_fichier.hpp:117
libdar::generic_file::read
virtual U_I read(char *a, U_I size) override
read data from the generic_file inherited from proto_generic_file
libdar::hash_fichier::get_position
virtual infinint get_position() const override
get the current read/write position
Definition: hash_fichier.hpp:104
libdar::hash_fichier::change_permission
virtual void change_permission(U_I perm) override
change the permission of the file
Definition: hash_fichier.hpp:95
libdar::fichier_global
abstraction of filesystem files for entrepot
Definition: fichier_global.hpp:58
libdar::hash_fichier::skip_relative
virtual bool skip_relative(S_I x) override
skip relatively to the current position
Definition: hash_fichier.hpp:103
libdar::hash_fichier::skip
virtual bool skip(const infinint &pos) override
skip at the absolute position
Definition: hash_fichier.hpp:101
libdar::hash_fichier::fichier_global_inherited_read
virtual bool fichier_global_inherited_read(char *a, U_I size, U_I &read, std::string &message) override
replaces generic_file::inherited_read() method, to allow the return of partial reading
libdar
libdar namespace encapsulate all libdar symbols
Definition: archive.hpp:46