1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/* Copyright 2024 Ján Sučan <jan@jansucan.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <endian.h>
#include <vector>
namespace FormatV2
{
const size_t RecordHeaderSize{sizeof(uint64_t) + sizeof(uint32_t)};
struct RecordData {
size_t size;
std::shared_ptr<char[]> data;
};
class Writer
{
public:
Writer(std::ostream &ostream, size_t buffer_size)
: m_writer{BufferedFile::Writer{ostream, buffer_size}} {};
void writeDiffRecord(
uint64_t offset, size_t size,
std::vector<RecordData> data) // cppcheck-suppress passedByValue
{
writeOffset(offset);
writeSize(size);
for (auto it = data.begin(); it != data.end(); ++it) {
writeData(*it);
}
}
private:
BufferedFile::Writer m_writer;
void writeOffset(uint64_t offset)
{
uint64_t val{htobe64(offset)};
m_writer.write(reinterpret_cast<char *>(&val), sizeof(val));
};
void writeSize(size_t size)
{
uint32_t val{htobe32(size)};
m_writer.write(reinterpret_cast<char *>(&val), sizeof(val));
};
void writeData(RecordData data)
{
m_writer.write(reinterpret_cast<char *>(data.data.get()), data.size);
};
};
class Reader
{
public:
Reader(std::istream &istream, size_t buffer_size)
: m_reader{BufferedFile::Reader{istream, buffer_size}}, m_eof{false} {};
bool eof() { return m_eof; };
uint64_t readOffset()
{
uint64_t raw_offset;
const size_t r{m_reader.read(reinterpret_cast<char *>(&raw_offset),
sizeof(raw_offset))};
if (r != sizeof(raw_offset)) {
m_eof = true;
}
return be64toh(raw_offset);
};
size_t readSize()
{
uint32_t raw_size;
const size_t r{m_reader.read(reinterpret_cast<char *>(&raw_size),
sizeof(raw_size))};
if (r != sizeof(raw_size)) {
m_eof = true;
}
return be32toh(raw_size);
};
size_t readData(size_t size, char **return_data)
{
return m_reader.tryRead(size, return_data);
};
private:
BufferedFile::Reader m_reader;
bool m_eof;
};
} // namespace FormatV2
|