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- //
- // detail/impl/service_registry.ipp
- // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- //
- // 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)
- //
-
- #ifndef ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
- #define ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
-
- #if defined(_MSC_VER) && (_MSC_VER >= 1200)
- # pragma once
- #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
- #include "asio/detail/config.hpp"
- #include <vector>
- #include "asio/detail/service_registry.hpp"
- #include "asio/detail/throw_exception.hpp"
-
- #include "asio/detail/push_options.hpp"
-
- namespace asio {
- namespace detail {
-
- service_registry::service_registry(execution_context& owner)
- : owner_(owner),
- first_service_(0)
- {
- }
-
- service_registry::~service_registry()
- {
- }
-
- void service_registry::shutdown_services()
- {
- execution_context::service* service = first_service_;
- while (service)
- {
- service->shutdown();
- service = service->next_;
- }
- }
-
- void service_registry::destroy_services()
- {
- while (first_service_)
- {
- execution_context::service* next_service = first_service_->next_;
- destroy(first_service_);
- first_service_ = next_service;
- }
- }
-
- void service_registry::notify_fork(execution_context::fork_event fork_ev)
- {
- // Make a copy of all of the services while holding the lock. We don't want
- // to hold the lock while calling into each service, as it may try to call
- // back into this class.
- std::vector<execution_context::service*> services;
- {
- asio::detail::mutex::scoped_lock lock(mutex_);
- execution_context::service* service = first_service_;
- while (service)
- {
- services.push_back(service);
- service = service->next_;
- }
- }
-
- // If processing the fork_prepare event, we want to go in reverse order of
- // service registration, which happens to be the existing order of the
- // services in the vector. For the other events we want to go in the other
- // direction.
- std::size_t num_services = services.size();
- if (fork_ev == execution_context::fork_prepare)
- for (std::size_t i = 0; i < num_services; ++i)
- services[i]->notify_fork(fork_ev);
- else
- for (std::size_t i = num_services; i > 0; --i)
- services[i - 1]->notify_fork(fork_ev);
- }
-
- void service_registry::init_key_from_id(execution_context::service::key& key,
- const execution_context::id& id)
- {
- key.type_info_ = 0;
- key.id_ = &id;
- }
-
- bool service_registry::keys_match(
- const execution_context::service::key& key1,
- const execution_context::service::key& key2)
- {
- if (key1.id_ && key2.id_)
- if (key1.id_ == key2.id_)
- return true;
- if (key1.type_info_ && key2.type_info_)
- if (*key1.type_info_ == *key2.type_info_)
- return true;
- return false;
- }
-
- void service_registry::destroy(execution_context::service* service)
- {
- delete service;
- }
-
- execution_context::service* service_registry::do_use_service(
- const execution_context::service::key& key,
- factory_type factory, void* owner)
- {
- asio::detail::mutex::scoped_lock lock(mutex_);
-
- // First see if there is an existing service object with the given key.
- execution_context::service* service = first_service_;
- while (service)
- {
- if (keys_match(service->key_, key))
- return service;
- service = service->next_;
- }
-
- // Create a new service object. The service registry's mutex is not locked
- // at this time to allow for nested calls into this function from the new
- // service's constructor.
- lock.unlock();
- auto_service_ptr new_service = { factory(owner) };
- new_service.ptr_->key_ = key;
- lock.lock();
-
- // Check that nobody else created another service object of the same type
- // while the lock was released.
- service = first_service_;
- while (service)
- {
- if (keys_match(service->key_, key))
- return service;
- service = service->next_;
- }
-
- // Service was successfully initialised, pass ownership to registry.
- new_service.ptr_->next_ = first_service_;
- first_service_ = new_service.ptr_;
- new_service.ptr_ = 0;
- return first_service_;
- }
-
- void service_registry::do_add_service(
- const execution_context::service::key& key,
- execution_context::service* new_service)
- {
- if (&owner_ != &new_service->context())
- asio::detail::throw_exception(invalid_service_owner());
-
- asio::detail::mutex::scoped_lock lock(mutex_);
-
- // Check if there is an existing service object with the given key.
- execution_context::service* service = first_service_;
- while (service)
- {
- if (keys_match(service->key_, key))
- asio::detail::throw_exception(service_already_exists());
- service = service->next_;
- }
-
- // Take ownership of the service object.
- new_service->key_ = key;
- new_service->next_ = first_service_;
- first_service_ = new_service;
- }
-
- bool service_registry::do_has_service(
- const execution_context::service::key& key) const
- {
- asio::detail::mutex::scoped_lock lock(mutex_);
-
- execution_context::service* service = first_service_;
- while (service)
- {
- if (keys_match(service->key_, key))
- return true;
- service = service->next_;
- }
-
- return false;
- }
-
- } // namespace detail
- } // namespace asio
-
- #include "asio/detail/pop_options.hpp"
-
- #endif // ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
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