mirror of
https://github.com/boostorg/asio.git
synced 2026-02-24 14:22:08 +00:00
ecca8406c0
The coro type is a C++20 coroutine primitive for resumable functions,
with the ability to combine both asynchronous waiting (co_await) and
yielding (co_yield) into a single, stateful control flow. For example:
#include <boostasio.hpp>
#include <boostasio/experimental/coro.hpp>
using boost::asio::ip::tcp;
boost::asio::experimental::coro<std::string> reader(tcp::socket& sock)
{
std::string buf;
while (sock.is_open())
{
std::size_t n = co_await boost::asio::async_read_until(
sock, boost::asio::dynamic_buffer(buf), '\n',
boost::asio::experimental::use_coro);
co_yield buf.substr(0, n);
buf.erase(0, n);
}
}
boost::asio::awaitable<void> consumer(tcp::socket sock)
{
auto r = reader(sock);
auto msg1 = co_await r.async_resume(boost::asio::use_awaitable);
std::cout << "Message 1: " << msg1.value_or("\n");
auto msg2 = co_await r.async_resume(boost::asio::use_awaitable);
std::cout << "Message 2: " << msg2.value_or("\n");
}
boost::asio::awaitable<void> listen(tcp::acceptor& acceptor)
{
for (;;)
{
co_spawn(
acceptor.get_executor(),
consumer(co_await acceptor.async_accept(boost::asio::use_awaitable)),
boost::asio::detached);
}
}
int main()
{
boost::asio::io_context ctx;
tcp::acceptor acceptor(ctx, {tcp::v4(), 54321});
co_spawn(ctx, listen(acceptor), boost::asio::detached);
ctx.run();
}
46 lines
1.0 KiB
C++
46 lines
1.0 KiB
C++
//
|
|
// experimental/coro/partial.cpp
|
|
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
//
|
|
// Copyright (c) 2021 Klemens D. Morgenstern
|
|
// (klemens dot morgenstern at gmx dot net)
|
|
//
|
|
// 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)
|
|
//
|
|
|
|
// Disable autolinking for unit tests.
|
|
#if !defined(BOOST_ALL_NO_LIB)
|
|
#define BOOST_ALL_NO_LIB 1
|
|
#endif // !defined(BOOST_ALL_NO_LIB)
|
|
|
|
// Test that header file is self-contained.
|
|
#include <boost/asio/experimental/coro.hpp>
|
|
|
|
#include <boost/asio/io_context.hpp>
|
|
#include "../../unit_test.hpp"
|
|
|
|
using namespace boost::asio::experimental;
|
|
|
|
namespace coro {
|
|
|
|
void partial()
|
|
{
|
|
boost::asio::io_context ctx;
|
|
bool ran = false;
|
|
auto p = detail::post_coroutine(ctx, [&]{ran = true;});
|
|
BOOST_ASIO_CHECK(!ran);
|
|
p.resume();
|
|
BOOST_ASIO_CHECK(!ran);
|
|
ctx.run();
|
|
BOOST_ASIO_CHECK(ran);
|
|
}
|
|
|
|
} // namespace coro
|
|
|
|
BOOST_ASIO_TEST_SUITE
|
|
(
|
|
"coro/partial",
|
|
BOOST_ASIO_TEST_CASE(::coro::partial)
|
|
)
|