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
|
//
// async_file_copy.cpp
// ~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2024 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include <iostream>
#include "asio.hpp"
#if defined(ASIO_HAS_FILE)
class file_copier
{
public:
file_copier(asio::io_context& io_context,
const char* from, const char* to)
: from_file_(io_context, from,
asio::stream_file::read_only),
to_file_(io_context, to,
asio::stream_file::write_only
| asio::stream_file::create
| asio::stream_file::truncate)
{
}
void start()
{
do_read();
}
private:
void do_read()
{
from_file_.async_read_some(asio::buffer(data_),
[this](std::error_code error, std::size_t n)
{
if (!error)
{
do_write(n);
}
else if (error != asio::error::eof)
{
std::cerr << "Error copying file: " << error.message() << "\n";
}
});
}
void do_write(std::size_t n)
{
asio::async_write(to_file_, asio::buffer(data_, n),
[this](std::error_code error, std::size_t /*n*/)
{
if (!error)
{
do_read();
}
else
{
std::cerr << "Error copying file: " << error.message() << "\n";
}
});
}
asio::stream_file from_file_;
asio::stream_file to_file_;
char data_[4096];
};
int main(int argc, char* argv[])
{
try
{
if (argc != 3)
{
std::cerr << "Usage: async_file_copy <from> <to>\n";
return 1;
}
asio::io_context io_context;
file_copier copier(io_context, argv[1], argv[2]);
copier.start();
io_context.run();
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
return 1;
}
return 0;
}
#else // defined(ASIO_HAS_FILE)
int main() {}
#endif // defined(ASIO_HAS_FILE)
|