base/fuchsia/scoped_service_binding.h

   1 // Copyright 2018 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_
   6 #define BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_
   7
   8 #include <lib/fidl/cpp/binding_set.h>
   9
  10 #include "base/bind.h"
  11 #include "base/fuchsia/service_directory.h"
  12
  13 namespace base {
  14 namespace fuchsia {
  15
  16 template <typename Interface>
  17 class ScopedServiceBinding {
  18  public:
  19   // |service_directory| and |impl| must outlive the binding.
  20   ScopedServiceBinding(ServiceDirectory* service_directory, Interface* impl)
  21       : directory_(service_directory), impl_(impl) {
  22     directory_->AddService(
  23         BindRepeating(&ScopedServiceBinding::BindClient, Unretained(this)));
  24   }
  25
  26   ~ScopedServiceBinding() { directory_->RemoveService(Interface::Name_); }
  27
  28   void SetOnLastClientCallback(base::OnceClosure on_last_client_callback) {
  29     on_last_client_callback_ = std::move(on_last_client_callback);
  30     bindings_.set_empty_set_handler(
  31         fit::bind_member(this, &ScopedServiceBinding::OnBindingSetEmpty));
  32   }
  33
  34   bool has_clients() const { return bindings_.size() != 0; }
  35
  36  private:
  37   void BindClient(fidl::InterfaceRequest<Interface> request) {
  38     bindings_.AddBinding(impl_, std::move(request));
  39   }
  40
  41   void OnBindingSetEmpty() {
  42     bindings_.set_empty_set_handler(nullptr);
  43     std::move(on_last_client_callback_).Run();
  44   }
  45
  46   ServiceDirectory* const directory_;
  47   Interface* const impl_;
  48   fidl::BindingSet<Interface> bindings_;
  49   base::OnceClosure on_last_client_callback_;
  50
  51   DISALLOW_COPY_AND_ASSIGN(ScopedServiceBinding);
  52 };
  53
  54 }  // namespace fuchsia
  55 }  // namespace base
  56
  57 #endif  // BASE_FUCHSIA_SCOPED_SERVICE_BINDING_H_