131 lines
3.0 KiB
C++
131 lines
3.0 KiB
C++
//
|
|
// connect_pair.cpp
|
|
// ~~~~~~~~~~~~~~~~
|
|
//
|
|
// Copyright (c) 2003-2019 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 <array>
|
|
#include <iostream>
|
|
#include <string>
|
|
#include <cctype>
|
|
#include <boost/asio.hpp>
|
|
#include <boost/thread/thread.hpp>
|
|
|
|
#if defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
|
|
|
|
using boost::asio::local::stream_protocol;
|
|
|
|
class uppercase_filter
|
|
{
|
|
public:
|
|
uppercase_filter(stream_protocol::socket sock)
|
|
: socket_(std::move(sock))
|
|
{
|
|
read();
|
|
}
|
|
|
|
private:
|
|
void read()
|
|
{
|
|
socket_.async_read_some(boost::asio::buffer(data_),
|
|
[this](boost::system::error_code ec, std::size_t size)
|
|
{
|
|
if (!ec)
|
|
{
|
|
// Compute result.
|
|
for (std::size_t i = 0; i < size; ++i)
|
|
data_[i] = std::toupper(data_[i]);
|
|
|
|
// Send result.
|
|
write(size);
|
|
}
|
|
else
|
|
{
|
|
throw boost::system::system_error(ec);
|
|
}
|
|
});
|
|
}
|
|
|
|
void write(std::size_t size)
|
|
{
|
|
boost::asio::async_write(socket_, boost::asio::buffer(data_, size),
|
|
[this](boost::system::error_code ec, std::size_t /*size*/)
|
|
{
|
|
if (!ec)
|
|
{
|
|
// Wait for request.
|
|
read();
|
|
}
|
|
else
|
|
{
|
|
throw boost::system::system_error(ec);
|
|
}
|
|
});
|
|
}
|
|
|
|
stream_protocol::socket socket_;
|
|
std::array<char, 512> data_;
|
|
};
|
|
|
|
int main()
|
|
{
|
|
try
|
|
{
|
|
boost::asio::io_context io_context;
|
|
|
|
// Create a connected pair and pass one end to a filter.
|
|
stream_protocol::socket socket(io_context);
|
|
stream_protocol::socket filter_socket(io_context);
|
|
boost::asio::local::connect_pair(socket, filter_socket);
|
|
uppercase_filter filter(std::move(filter_socket));
|
|
|
|
// The io_context runs in a background thread to perform filtering.
|
|
boost::thread thread(
|
|
[&io_context]()
|
|
{
|
|
try
|
|
{
|
|
io_context.run();
|
|
}
|
|
catch (std::exception& e)
|
|
{
|
|
std::cerr << "Exception in thread: " << e.what() << "\n";
|
|
std::exit(1);
|
|
}
|
|
});
|
|
|
|
for (;;)
|
|
{
|
|
// Collect request from user.
|
|
std::cout << "Enter a string: ";
|
|
std::string request;
|
|
std::getline(std::cin, request);
|
|
|
|
// Send request to filter.
|
|
boost::asio::write(socket, boost::asio::buffer(request));
|
|
|
|
// Wait for reply from filter.
|
|
std::vector<char> reply(request.size());
|
|
boost::asio::read(socket, boost::asio::buffer(reply));
|
|
|
|
// Show reply to user.
|
|
std::cout << "Result: ";
|
|
std::cout.write(&reply[0], request.size());
|
|
std::cout << std::endl;
|
|
}
|
|
}
|
|
catch (std::exception& e)
|
|
{
|
|
std::cerr << "Exception: " << e.what() << "\n";
|
|
std::exit(1);
|
|
}
|
|
}
|
|
|
|
#else // defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
|
|
# error Local sockets not available on this platform.
|
|
#endif // defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
|