Disk ARchive 2.7.10
Full featured and portable backup and archiving tool
generic_rsync.hpp
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1/*********************************************************************/
2// dar - disk archive - a backup/restoration program
3// Copyright (C) 2002-2023 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18//
19// to contact the author, see the AUTHOR file
20/*********************************************************************/
21
25
26
27#ifndef GENERIC_RSYNC_HPP
28#define GENERIC_RSYNC_HPP
29
30#include "../my_config.h"
31
32extern "C"
33{
34#if HAVE_LIBRSYNC_H
35#include <librsync.h>
36#endif
37}
38
39#include "generic_file.hpp"
40#include "erreurs.hpp"
41
42namespace libdar
43{
44
47
49
51 {
52 public:
54
61 generic_rsync(generic_file *signature_storage,
62 U_I signature_block_size,
63 generic_file *below);
64
66
78 generic_rsync(generic_file *base_signature,
79 generic_file *below,
80 const infinint & crc_size,
81 const crc **checksum);
82
84
94 generic_file *delta);
95
96
97 generic_rsync(const generic_rsync & ref) = delete;
98 generic_rsync(generic_rsync && ref) noexcept = delete;
99 generic_rsync & operator = (const generic_rsync & ref) = delete;
100 generic_rsync & operator = (generic_rsync && ref) noexcept = delete;
101
102 ~generic_rsync() noexcept(false);
103
104 // inherited from generic_file
105
106 virtual bool skippable(skippability direction, const infinint & amount) override { return false; };
107 virtual bool skip(const infinint & pos) override {if(pos != 0 || !initial) throw SRC_BUG; else return true; };
108 virtual bool skip_to_eof() override { throw SRC_BUG; };
109 virtual bool skip_relative(S_I x) override { if(x != 0) throw SRC_BUG; else return true; };
110 virtual bool truncatable(const infinint & pos) const override { return pos == get_position(); };
111 virtual infinint get_position() const override { return x_below->get_position(); };
112
113 protected:
114 virtual void inherited_read_ahead(const infinint & amount) override {};
115 virtual U_I inherited_read(char *a, U_I size) override;
116 virtual void inherited_write(const char *a, U_I size) override;
117 virtual void inherited_truncate(const infinint & pos) override { if(pos != get_position()) throw SRC_BUG; };
118 virtual void inherited_sync_write() override {};
119 virtual void inherited_flush_read() override {};
120 virtual void inherited_terminate() override;
121
122 private:
123 enum { sign, delta, patch } status;
124
126 generic_file *x_input;
127 generic_file *x_output;
128 bool initial;
129 char *working_buffer;
130 U_I working_size;
131 bool patching_completed;
132 crc *data_crc;
133
134#if LIBRSYNC_AVAILABLE
135 rs_job_t *job;
136 rs_signature_t *sumset;
137
139 static rs_result patch_callback(void *opaque,
140 rs_long_t pos,
141 size_t *len,
142 void **buf);
143#endif
144
146
156 bool step_forward(const char *buffer_in,
157 U_I & avail_in,
158 bool shift_input,
159 char *buffer_out,
160 U_I & avail_out);
161 void free_job();
162 void send_eof();
163 };
164
166
167} // end of namespace
168
169#endif
pure virtual class defining interface of a CRC object
Definition: crc.hpp:47
this is the interface class from which all other data transfer classes inherit
virtual infinint get_position() const =0
get the current read/write position
generic_file interface to librsync
virtual void inherited_flush_read() override
reset internal engine, flush caches in order to read the data at current position
virtual void inherited_truncate(const infinint &pos) override
truncate file at the give offset
virtual void inherited_terminate() override
destructor-like call, except that it is allowed to throw exceptions
virtual bool skippable(skippability direction, const infinint &amount) override
whether the implementation is able to skip
virtual infinint get_position() const override
get the current read/write position
generic_rsync(generic_file *signature_storage, U_I signature_block_size, generic_file *below)
constructor for "signature" operation
virtual bool skip(const infinint &pos) override
skip at the absolute position
virtual void inherited_sync_write() override
write down any pending data
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...
generic_rsync(generic_file *current_data, generic_file *delta)
constructor for "patch" operation
generic_rsync(generic_file *base_signature, generic_file *below, const infinint &crc_size, const crc **checksum)
constructor for "delta" operation
bool step_forward(const char *buffer_in, U_I &avail_in, bool shift_input, char *buffer_out, U_I &avail_out)
feed librsync using rs_job_iter
virtual U_I inherited_read(char *a, U_I size) override
implementation of read() operation
virtual bool skip_to_eof() override
skip to the end of file
virtual void inherited_write(const char *a, U_I size) override
implementation of the write() operation
virtual bool skip_relative(S_I x) override
skip relatively to the current position
generic_file * x_below
underlying layer to read from / write to
virtual bool truncatable(const infinint &pos) const override
whether the implementation is able to truncate to the given position
the arbitrary large positive integer class
contains all the excetion class thrown by libdar
class generic_file is defined here as well as class fichier
libdar namespace encapsulate all libdar symbols
Definition: archive.hpp:47