summaryrefslogtreecommitdiffstatshomepage
path: root/3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp
diff options
context:
space:
mode:
Diffstat (limited to '3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp')
-rw-r--r--3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp201
1 files changed, 201 insertions, 0 deletions
diff --git a/3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp b/3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp
new file mode 100644
index 00000000000..45b56cb0263
--- /dev/null
+++ b/3rdparty/asio/src/examples/cpp03/timeouts/blocking_token_tcp_client.cpp
@@ -0,0 +1,201 @@
+//
+// blocking_token_tcp_client.cpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2021 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 "asio/connect.hpp"
+#include "asio/io_context.hpp"
+#include "asio/ip/tcp.hpp"
+#include "asio/read_until.hpp"
+#include "asio/streambuf.hpp"
+#include "asio/system_error.hpp"
+#include "asio/write.hpp"
+#include <cstdlib>
+#include <iostream>
+#include <memory>
+#include <string>
+
+using asio::ip::tcp;
+
+// We will use our sockets only with an io_context.
+typedef asio::basic_stream_socket<tcp,
+ asio::io_context::executor_type> tcp_socket;
+
+//----------------------------------------------------------------------
+
+// A custom completion token that makes asynchronous operations behave as
+// though they are blocking calls with a timeout.
+struct close_after
+{
+ close_after(asio::chrono::steady_clock::duration t, tcp_socket& s)
+ : timeout_(t), socket_(s)
+ {
+ }
+
+ // The maximum time to wait for an asynchronous operation to complete.
+ asio::chrono::steady_clock::duration timeout_;
+
+ // The socket to be closed if the operation does not complete in time.
+ tcp_socket& socket_;
+};
+
+namespace asio {
+
+// The async_result template is specialised to allow the close_after token to
+// be used with asynchronous operations that have a completion signature of
+// void(error_code, T). Generalising this for all completion signature forms is
+// left as an exercise for the reader.
+template <typename T>
+class async_result<close_after, void(asio::error_code, T)>
+{
+public:
+ // An asynchronous operation's initiating function automatically creates an
+ // completion_handler_type object from the token. This function object is
+ // then called on completion of the asynchronous operation.
+ class completion_handler_type
+ {
+ public:
+ completion_handler_type(const close_after& token)
+ : token_(token)
+ {
+ }
+
+ void operator()(asio::error_code ec, T t)
+ {
+ *ec_ = ec;
+ *t_ = t;
+ }
+
+ private:
+ friend class async_result;
+ close_after token_;
+ asio::error_code* ec_;
+ T* t_;
+ };
+
+ // The async_result constructor associates the completion handler object with
+ // the result of the initiating function.
+ explicit async_result(completion_handler_type& h)
+ : timeout_(h.token_.timeout_),
+ socket_(h.token_.socket_)
+ {
+ h.ec_ = &ec_;
+ h.t_ = &t_;
+ }
+
+ // The return_type typedef determines the result type of the asynchronous
+ // operation's initiating function.
+ typedef T return_type;
+
+ // The get() function is used to obtain the result of the asynchronous
+ // operation's initiating function. For the close_after completion token, we
+ // use this function to run the io_context until the operation is complete.
+ return_type get()
+ {
+ asio::io_context& io_context = asio::query(
+ socket_.get_executor(), asio::execution::context);
+
+ // Restart the io_context, as it may have been left in the "stopped" state
+ // by a previous operation.
+ io_context.restart();
+
+ // Block until the asynchronous operation has completed, or timed out. If
+ // the pending asynchronous operation is a composed operation, the deadline
+ // applies to the entire operation, rather than individual operations on
+ // the socket.
+ io_context.run_for(timeout_);
+
+ // If the asynchronous operation completed successfully then the io_context
+ // would have been stopped due to running out of work. If it was not
+ // stopped, then the io_context::run_for call must have timed out and the
+ // operation is still incomplete.
+ if (!io_context.stopped())
+ {
+ // Close the socket to cancel the outstanding asynchronous operation.
+ socket_.close();
+
+ // Run the io_context again until the operation completes.
+ io_context.run();
+ }
+
+ // If the operation failed, throw an exception. Otherwise return the result.
+ return ec_ ? throw asio::system_error(ec_) : t_;
+ }
+
+private:
+ asio::chrono::steady_clock::duration timeout_;
+ tcp_socket& socket_;
+ asio::error_code ec_;
+ T t_;
+};
+
+} // namespace asio
+
+//----------------------------------------------------------------------
+
+int main(int argc, char* argv[])
+{
+ try
+ {
+ if (argc != 4)
+ {
+ std::cerr << "Usage: blocking_tcp_client <host> <port> <message>\n";
+ return 1;
+ }
+
+ asio::io_context io_context;
+
+ // Resolve the host name and service to a list of endpoints.
+ tcp::resolver::results_type endpoints =
+ tcp::resolver(io_context).resolve(argv[1], argv[2]);
+
+ tcp_socket socket(io_context);
+
+ // Run an asynchronous connect operation with a timeout.
+ asio::async_connect(socket, endpoints,
+ close_after(asio::chrono::seconds(10), socket));
+
+ asio::chrono::steady_clock::time_point time_sent =
+ asio::chrono::steady_clock::now();
+
+ // Run an asynchronous write operation with a timeout.
+ std::string msg = argv[3] + std::string("\n");
+ asio::async_write(socket, asio::buffer(msg),
+ close_after(asio::chrono::seconds(10), socket));
+
+ for (std::string input_buffer;;)
+ {
+ // Run an asynchronous read operation with a timeout.
+ std::size_t n = asio::async_read_until(socket,
+ asio::dynamic_buffer(input_buffer), '\n',
+ close_after(asio::chrono::seconds(10), socket));
+
+ std::string line(input_buffer.substr(0, n - 1));
+ input_buffer.erase(0, n);
+
+ // Keep going until we get back the line that was sent.
+ if (line == argv[3])
+ break;
+ }
+
+ asio::chrono::steady_clock::time_point time_received =
+ asio::chrono::steady_clock::now();
+
+ std::cout << "Round trip time: ";
+ std::cout << asio::chrono::duration_cast<
+ asio::chrono::microseconds>(
+ time_received - time_sent).count();
+ std::cout << " microseconds\n";
+ }
+ catch (std::exception& e)
+ {
+ std::cerr << "Exception: " << e.what() << "\n";
+ }
+
+ return 0;
+}