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
|
/*
* This file is open source software, licensed to you under the terms
* of the Apache License, Version 2.0 (the "License"). See the NOTICE file
* distributed with this work for additional information regarding copyright
* ownership. You may not use this file except in compliance with the License.
*
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
/*
* Copyright (C) 2019 ScyllaDB Ltd.
*/
#include <iostream>
#include <seastar/util/std-compat.hh>
#ifndef SEASTAR_COROUTINES_ENABLED
int main(int argc, char** argv) {
std::cout << "coroutines not available\n";
return 0;
}
#else
#include <seastar/core/app-template.hh>
#include <seastar/core/coroutine.hh>
#include <seastar/core/fstream.hh>
#include <seastar/core/sleep.hh>
#include <seastar/core/seastar.hh>
#include <seastar/core/loop.hh>
#include <seastar/core/sstring.hh>
#include <seastar/coroutine/parallel_for_each.hh>
int main(int argc, char** argv) {
seastar::app_template app;
app.run(argc, argv, [] () -> seastar::future<> {
std::cout << "this is a completely useless program\nplease stand by...\n";
auto f = seastar::coroutine::parallel_for_each(std::vector<int> { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }, [] (int i) -> seastar::future<> {
co_await seastar::sleep(std::chrono::seconds(i));
std::cout << i << "\n";
});
auto file = co_await seastar::open_file_dma("useless_file.txt", seastar::open_flags::create | seastar::open_flags::wo);
auto out = co_await seastar::make_file_output_stream(file);
seastar::sstring str = "nothing to see here, move along now\n";
co_await out.write(str);
co_await out.flush();
co_await out.close();
bool all_exist = true;
std::vector<seastar::sstring> filenames = { "useless_file.txt", "non_existing" };
co_await seastar::coroutine::parallel_for_each(filenames, [&all_exist] (const seastar::sstring& name) -> seastar::future<> {
all_exist &= co_await seastar::file_exists(name);
});
std::cout << (all_exist ? "" : "not ") << "all files exist" << std::endl;
co_await std::move(f);
std::cout << "done\n";
});
}
#endif
|
