blob: 310163f706cdc4c2d0436083c01c6e882d2ce15a (
plain) (
blame)
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
|
#pragma once
#include <boost/filesystem.hpp>
#include <boost/program_options.hpp>
#include <exception>
#include <iostream>
#include <string>
#include <thread>
#include <vector>
namespace math::server {
struct Settings {
static constexpr unsigned DEFAULT_PORT = 18000;
static unsigned default_threads() { return std::thread::hardware_concurrency(); }
unsigned m_port;
unsigned m_threads;
bool exit_with_usage() const { return m_vm.count("help"); }
boost::program_options::variables_map m_vm;
};
class SettingsParser {
public:
explicit SettingsParser(const std::string& argv0)
: m_prog_name{extract_filename(argv0)}
{
m_visible.add_options()
("help,h",
"show this message and exit")
("port,p",
boost::program_options::value(&m_settings.m_port)->default_value(Settings::DEFAULT_PORT),
"server port number")
("threads,n",
boost::program_options::value(&m_settings.m_threads)->default_value(Settings::default_threads()),
"number of threads");
}
static const char* get_short_description() {
return "[-h|--help] [-p|--port] [-n|--threads]";
}
Settings parse(int argc, char* argv[]) {
boost::program_options::store(
boost::program_options::command_line_parser{argc, argv}
.options(m_visible)
.run(),
m_settings.m_vm);
if (m_settings.exit_with_usage()) {
return m_settings;
}
boost::program_options::notify(m_settings.m_vm);
return m_settings;
}
void usage() const {
std::cout << *this;
}
void usage_error(const std::exception& e) const {
std::cerr << "usage error: " << e.what() << '\n';
std::cerr << *this;
}
private:
static std::string extract_filename(const std::string& path) {
return boost::filesystem::path{path}.filename().string();
}
const std::string m_prog_name;
boost::program_options::options_description m_visible;
Settings m_settings;
friend std::ostream& operator<<(std::ostream& os, const SettingsParser& parser) {
os << "usage: " << parser.m_prog_name << ' ' << get_short_description() << '\n';
os << parser.m_visible;
return os;
}
};
}
|
