// Copyright 2018 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_ #define BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_ #include #include #include #include #include #include "base/base_export.h" #include "base/callback.h" #include "base/fuchsia/scoped_service_publisher.h" #include "third_party/abseil-cpp/absl/types/optional.h" namespace sys { class OutgoingDirectory; } // namespace sys namespace vfs { class PseudoDir; } // namespace vfs namespace base { template class BASE_EXPORT ScopedServiceBinding { public: // Published a public service in the specified |outgoing_directory|. // |outgoing_directory| and |impl| must outlive the binding. ScopedServiceBinding(sys::OutgoingDirectory* outgoing_directory, Interface* impl, base::StringPiece name = Interface::Name_) : publisher_(outgoing_directory, bindings_.GetHandler(impl), name) {} // Publishes a service in the specified |pseudo_dir|. |pseudo_dir| and |impl| // must outlive the binding. ScopedServiceBinding(vfs::PseudoDir* pseudo_dir, Interface* impl, base::StringPiece name = Interface::Name_) : publisher_(pseudo_dir, bindings_.GetHandler(impl), name) {} ScopedServiceBinding(const ScopedServiceBinding&) = delete; ScopedServiceBinding& operator=(const ScopedServiceBinding&) = delete; ~ScopedServiceBinding() = default; // |on_last_client_callback| will be called every time the number of connected // clients drops to 0. void SetOnLastClientCallback(base::RepeatingClosure on_last_client_callback) { bindings_.set_empty_set_handler( [callback = std::move(on_last_client_callback)] { callback.Run(); }); } bool has_clients() const { return bindings_.size() != 0; } private: fidl::BindingSet bindings_; ScopedServicePublisher publisher_; }; // Scoped service binding which allows only a single client to be connected // at any time. By default a new connection will disconnect an existing client. enum class ScopedServiceBindingPolicy { kPreferNew, kPreferExisting, kConnectOnce }; template class BASE_EXPORT ScopedSingleClientServiceBinding { public: // |outgoing_directory| and |impl| must outlive the binding. ScopedSingleClientServiceBinding(sys::OutgoingDirectory* outgoing_directory, Interface* impl, base::StringPiece name = Interface::Name_) : binding_(impl) { publisher_.emplace( outgoing_directory, fit::bind_member(this, &ScopedSingleClientServiceBinding::BindClient), name); binding_.set_error_handler(fit::bind_member( this, &ScopedSingleClientServiceBinding::OnBindingEmpty)); } ScopedSingleClientServiceBinding(const ScopedSingleClientServiceBinding&) = delete; ScopedSingleClientServiceBinding& operator=( const ScopedSingleClientServiceBinding&) = delete; ~ScopedSingleClientServiceBinding() = default; typename Interface::EventSender_& events() { return binding_.events(); } // |on_last_client_callback| will be called the first time a client // disconnects. It is still possible for a client to connect after that point // if Policy is kPreferNew of kPreferExisting. void SetOnLastClientCallback(base::OnceClosure on_last_client_callback) { on_last_client_callback_ = std::move(on_last_client_callback); } bool has_clients() const { return binding_.is_bound(); } private: void BindClient(fidl::InterfaceRequest request) { if (Policy == ScopedServiceBindingPolicy::kPreferExisting && binding_.is_bound()) { return; } binding_.Bind(std::move(request)); if (Policy == ScopedServiceBindingPolicy::kConnectOnce) { publisher_.reset(); } } void OnBindingEmpty(zx_status_t status) { if (on_last_client_callback_) { std::move(on_last_client_callback_).Run(); } } fidl::Binding binding_; absl::optional> publisher_; base::OnceClosure on_last_client_callback_; }; } // namespace base #endif // BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_