boost/asio/detail/service_registry.hpp
//
// detail/service_registry.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2023 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)
//
#ifndef BOOST_ASIO_DETAIL_SERVICE_REGISTRY_HPP
#define BOOST_ASIO_DETAIL_SERVICE_REGISTRY_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <typeinfo>
#include <boost/asio/detail/mutex.hpp>
#include <boost/asio/detail/noncopyable.hpp>
#include <boost/asio/detail/type_traits.hpp>
#include <boost/asio/execution_context.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
class io_context;
namespace detail {
template <typename T>
class typeid_wrapper {};
class service_registry
: private noncopyable
{
public:
// Constructor.
BOOST_ASIO_DECL service_registry(execution_context& owner);
// Destructor.
BOOST_ASIO_DECL ~service_registry();
// Shutdown all services.
BOOST_ASIO_DECL void shutdown_services();
// Destroy all services.
BOOST_ASIO_DECL void destroy_services();
// Notify all services of a fork event.
BOOST_ASIO_DECL void notify_fork(execution_context::fork_event fork_ev);
// Get the service object corresponding to the specified service type. Will
// create a new service object automatically if no such object already
// exists. Ownership of the service object is not transferred to the caller.
template <typename Service>
Service& use_service();
// Get the service object corresponding to the specified service type. Will
// create a new service object automatically if no such object already
// exists. Ownership of the service object is not transferred to the caller.
// This overload is used for backwards compatibility with services that
// inherit from io_context::service.
template <typename Service>
Service& use_service(io_context& owner);
// Add a service object. Throws on error, in which case ownership of the
// object is retained by the caller.
template <typename Service>
void add_service(Service* new_service);
// Check whether a service object of the specified type already exists.
template <typename Service>
bool has_service() const;
private:
// Initalise a service's key when the key_type typedef is not available.
template <typename Service>
static void init_key(execution_context::service::key& key, ...);
#if !defined(BOOST_ASIO_NO_TYPEID)
// Initalise a service's key when the key_type typedef is available.
template <typename Service>
static void init_key(execution_context::service::key& key,
enable_if_t<is_base_of<typename Service::key_type, Service>::value>*);
#endif // !defined(BOOST_ASIO_NO_TYPEID)
// Initialise a service's key based on its id.
BOOST_ASIO_DECL static void init_key_from_id(
execution_context::service::key& key,
const execution_context::id& id);
#if !defined(BOOST_ASIO_NO_TYPEID)
// Initialise a service's key based on its id.
template <typename Service>
static void init_key_from_id(execution_context::service::key& key,
const service_id<Service>& /*id*/);
#endif // !defined(BOOST_ASIO_NO_TYPEID)
// Check if a service matches the given id.
BOOST_ASIO_DECL static bool keys_match(
const execution_context::service::key& key1,
const execution_context::service::key& key2);
// The type of a factory function used for creating a service instance.
typedef execution_context::service*(*factory_type)(void*);
// Factory function for creating a service instance.
template <typename Service, typename Owner>
static execution_context::service* create(void* owner);
// Destroy a service instance.
BOOST_ASIO_DECL static void destroy(execution_context::service* service);
// Helper class to manage service pointers.
struct auto_service_ptr;
friend struct auto_service_ptr;
struct auto_service_ptr
{
execution_context::service* ptr_;
~auto_service_ptr() { destroy(ptr_); }
};
// Get the service object corresponding to the specified service key. Will
// create a new service object automatically if no such object already
// exists. Ownership of the service object is not transferred to the caller.
BOOST_ASIO_DECL execution_context::service* do_use_service(
const execution_context::service::key& key,
factory_type factory, void* owner);
// Add a service object. Throws on error, in which case ownership of the
// object is retained by the caller.
BOOST_ASIO_DECL void do_add_service(
const execution_context::service::key& key,
execution_context::service* new_service);
// Check whether a service object with the specified key already exists.
BOOST_ASIO_DECL bool do_has_service(
const execution_context::service::key& key) const;
// Mutex to protect access to internal data.
mutable boost::asio::detail::mutex mutex_;
// The owner of this service registry and the services it contains.
execution_context& owner_;
// The first service in the list of contained services.
execution_context::service* first_service_;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#include <boost/asio/detail/impl/service_registry.hpp>
#if defined(BOOST_ASIO_HEADER_ONLY)
# include <boost/asio/detail/impl/service_registry.ipp>
#endif // defined(BOOST_ASIO_HEADER_ONLY)
#endif // BOOST_ASIO_DETAIL_SERVICE_REGISTRY_HPP