// server.cpp
// ~~~~~~~~~~
//
-// Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+// Copyright (c) 2003-2017 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)
// It contains a single block of memory which may be returned for allocation
// requests. If the memory is in use when an allocation request is made, the
// allocator delegates allocation to the global heap.
-class handler_allocator
+class handler_memory
: private boost::noncopyable
{
public:
- handler_allocator()
+ handler_memory()
: in_use_(false)
{
}
bool in_use_;
};
+// The allocator to be associated with the handler objects. This allocator only
+// needs to satisfy the C++11 minimal allocator requirements, plus rebind when
+// targeting C++03.
+template <typename T>
+class handler_allocator
+{
+public:
+ typedef T value_type;
+
+ explicit handler_allocator(handler_memory& mem)
+ : memory_(mem)
+ {
+ }
+
+ template <typename U>
+ handler_allocator(const handler_allocator<U>& other)
+ : memory_(other.memory_)
+ {
+ }
+
+ template <typename U>
+ struct rebind
+ {
+ typedef handler_allocator<U> other;
+ };
+
+ bool operator==(const handler_allocator& other) const
+ {
+ return &memory_ == &other.memory_;
+ }
+
+ bool operator!=(const handler_allocator& other) const
+ {
+ return &memory_ != &other.memory_;
+ }
+
+ T* allocate(std::size_t n) const
+ {
+ return static_cast<T*>(memory_.allocate(sizeof(T) * n));
+ }
+
+ void deallocate(T* p, std::size_t /*n*/) const
+ {
+ return memory_.deallocate(p);
+ }
+
+//private:
+ // The underlying memory.
+ handler_memory& memory_;
+};
+
// Wrapper class template for handler objects to allow handler memory
-// allocation to be customised. Calls to operator() are forwarded to the
-// encapsulated handler.
+// allocation to be customised. The allocator_type typedef and get_allocator()
+// member function are used by the asynchronous operations to obtain the
+// allocator. Calls to operator() are forwarded to the encapsulated handler.
template <typename Handler>
class custom_alloc_handler
{
public:
- custom_alloc_handler(handler_allocator& a, Handler h)
- : allocator_(a),
+ typedef handler_allocator<Handler> allocator_type;
+
+ custom_alloc_handler(handler_memory& m, Handler h)
+ : memory_(m),
handler_(h)
{
}
+ allocator_type get_allocator() const
+ {
+ return allocator_type(memory_);
+ }
+
template <typename Arg1>
void operator()(Arg1 arg1)
{
handler_(arg1, arg2);
}
- friend void* asio_handler_allocate(std::size_t size,
- custom_alloc_handler<Handler>* this_handler)
- {
- return this_handler->allocator_.allocate(size);
- }
-
- friend void asio_handler_deallocate(void* pointer, std::size_t /*size*/,
- custom_alloc_handler<Handler>* this_handler)
- {
- this_handler->allocator_.deallocate(pointer);
- }
-
private:
- handler_allocator& allocator_;
+ handler_memory& memory_;
Handler handler_;
};
// Helper function to wrap a handler object to add custom allocation.
template <typename Handler>
inline custom_alloc_handler<Handler> make_custom_alloc_handler(
- handler_allocator& a, Handler h)
+ handler_memory& m, Handler h)
{
- return custom_alloc_handler<Handler>(a, h);
+ return custom_alloc_handler<Handler>(m, h);
}
class session
: public boost::enable_shared_from_this<session>
{
public:
- session(boost::asio::io_service& io_service)
- : socket_(io_service)
+ session(boost::asio::io_context& io_context)
+ : socket_(io_context)
{
}
void start()
{
socket_.async_read_some(boost::asio::buffer(data_),
- make_custom_alloc_handler(allocator_,
+ make_custom_alloc_handler(handler_memory_,
boost::bind(&session::handle_read,
shared_from_this(),
boost::asio::placeholders::error,
{
boost::asio::async_write(socket_,
boost::asio::buffer(data_, bytes_transferred),
- make_custom_alloc_handler(allocator_,
+ make_custom_alloc_handler(handler_memory_,
boost::bind(&session::handle_write,
shared_from_this(),
boost::asio::placeholders::error)));
if (!error)
{
socket_.async_read_some(boost::asio::buffer(data_),
- make_custom_alloc_handler(allocator_,
+ make_custom_alloc_handler(handler_memory_,
boost::bind(&session::handle_read,
shared_from_this(),
boost::asio::placeholders::error,
// Buffer used to store data received from the client.
boost::array<char, 1024> data_;
- // The allocator to use for handler-based custom memory allocation.
- handler_allocator allocator_;
+ // The memory to use for handler-based custom memory allocation.
+ handler_memory handler_memory_;
};
typedef boost::shared_ptr<session> session_ptr;
class server
{
public:
- server(boost::asio::io_service& io_service, short port)
- : io_service_(io_service),
- acceptor_(io_service, tcp::endpoint(tcp::v4(), port))
+ server(boost::asio::io_context& io_context, short port)
+ : io_context_(io_context),
+ acceptor_(io_context, tcp::endpoint(tcp::v4(), port))
{
- session_ptr new_session(new session(io_service_));
+ session_ptr new_session(new session(io_context_));
acceptor_.async_accept(new_session->socket(),
boost::bind(&server::handle_accept, this, new_session,
boost::asio::placeholders::error));
new_session->start();
}
- new_session.reset(new session(io_service_));
+ new_session.reset(new session(io_context_));
acceptor_.async_accept(new_session->socket(),
boost::bind(&server::handle_accept, this, new_session,
boost::asio::placeholders::error));
}
private:
- boost::asio::io_service& io_service_;
+ boost::asio::io_context& io_context_;
tcp::acceptor acceptor_;
};
return 1;
}
- boost::asio::io_service io_service;
+ boost::asio::io_context io_context;
using namespace std; // For atoi.
- server s(io_service, atoi(argv[1]));
+ server s(io_context, atoi(argv[1]));
- io_service.run();
+ io_context.run();
}
catch (std::exception& e)
{