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Diffstat (limited to '3rdparty/asio/src/examples/cpp03/http/server4/server.cpp')
-rw-r--r-- | 3rdparty/asio/src/examples/cpp03/http/server4/server.cpp | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/3rdparty/asio/src/examples/cpp03/http/server4/server.cpp b/3rdparty/asio/src/examples/cpp03/http/server4/server.cpp new file mode 100644 index 00000000000..04d81a984b6 --- /dev/null +++ b/3rdparty/asio/src/examples/cpp03/http/server4/server.cpp @@ -0,0 +1,122 @@ +// +// server.cpp +// ~~~~~~~~~~ +// +// Copyright (c) 2003-2016 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 "server.hpp" +#include "request.hpp" +#include "reply.hpp" + +namespace http { +namespace server4 { + +server::server(asio::io_context& io_context, + const std::string& address, const std::string& port, + boost::function<void(const request&, reply&)> request_handler) + : request_handler_(request_handler) +{ + tcp::resolver resolver(io_context); + asio::ip::tcp::endpoint endpoint = + *resolver.resolve(address, port).begin(); + acceptor_.reset(new tcp::acceptor(io_context, endpoint)); +} + +// Enable the pseudo-keywords reenter, yield and fork. +#include <asio/yield.hpp> + +void server::operator()(asio::error_code ec, std::size_t length) +{ + // In this example we keep the error handling code in one place by + // hoisting it outside the coroutine. An alternative approach would be to + // check the value of ec after each yield for an asynchronous operation. + if (!ec) + { + // On reentering a coroutine, control jumps to the location of the last + // yield or fork. The argument to the "reenter" pseudo-keyword can be a + // pointer or reference to an object of type coroutine. + reenter (this) + { + // Loop to accept incoming connections. + do + { + // Create a new socket for the next incoming connection. + socket_.reset(new tcp::socket(acceptor_->get_executor().context())); + + // Accept a new connection. The "yield" pseudo-keyword saves the current + // line number and exits the coroutine's "reenter" block. We use the + // server coroutine as the completion handler for the async_accept + // operation. When the asynchronous operation completes, the io_context + // invokes the function call operator, we "reenter" the coroutine, and + // then control resumes at the following line. + yield acceptor_->async_accept(*socket_, *this); + + // We "fork" by cloning a new server coroutine to handle the connection. + // After forking we have a parent coroutine and a child coroutine. Both + // parent and child continue execution at the following line. They can + // be distinguished using the functions coroutine::is_parent() and + // coroutine::is_child(). + fork server(*this)(); + + // The parent continues looping to accept the next incoming connection. + // The child exits the loop and processes the connection. + } while (is_parent()); + + // Create the objects needed to receive a request on the connection. + buffer_.reset(new boost::array<char, 8192>); + request_.reset(new request); + + // Loop until a complete request (or an invalid one) has been received. + do + { + // Receive some more data. When control resumes at the following line, + // the ec and length parameters reflect the result of the asynchronous + // operation. + yield socket_->async_read_some(asio::buffer(*buffer_), *this); + + // Parse the data we just received. + boost::tie(valid_request_, boost::tuples::ignore) + = request_parser_.parse(*request_, + buffer_->data(), buffer_->data() + length); + + // An indeterminate result means we need more data, so keep looping. + } while (boost::indeterminate(valid_request_)); + + // Create the reply object that will be sent back to the client. + reply_.reset(new reply); + + if (valid_request_) + { + // A valid request was received. Call the user-supplied function object + // to process the request and compose a reply. + request_handler_(*request_, *reply_); + } + else + { + // The request was invalid. + *reply_ = reply::stock_reply(reply::bad_request); + } + + // Send the reply back to the client. + yield asio::async_write(*socket_, reply_->to_buffers(), *this); + + // Initiate graceful connection closure. + socket_->shutdown(tcp::socket::shutdown_both, ec); + } + } + + // If an error occurs then the coroutine is not reentered. Consequently, no + // new asynchronous operations are started. This means that all shared_ptr + // references will disappear and the resources associated with the coroutine + // will be destroyed automatically after this function call returns. +} + +// Disable the pseudo-keywords reenter, yield and fork. +#include <asio/unyield.hpp> + +} // namespace server4 +} // namespace http |