Mojo C++ bindings: InterfacePtr<T> and Binding<T> use MultiplexRouter when T passes associated inte…

mojo/public/cpp/bindings/lib/binding_state.h

+// Copyright 2015 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 MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDING_STATE_H_
+#define MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDING_STATE_H_
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "mojo/public/c/environment/async_waiter.h"
+#include "mojo/public/cpp/bindings/associated_group.h"
+#include "mojo/public/cpp/bindings/callback.h"
+#include "mojo/public/cpp/bindings/interface_ptr.h"
+#include "mojo/public/cpp/bindings/interface_ptr_info.h"
+#include "mojo/public/cpp/bindings/interface_request.h"
+#include "mojo/public/cpp/bindings/lib/filter_chain.h"
+#include "mojo/public/cpp/bindings/lib/interface_endpoint_client.h"
+#include "mojo/public/cpp/bindings/lib/interface_id.h"
+#include "mojo/public/cpp/bindings/lib/message_header_validator.h"
+#include "mojo/public/cpp/bindings/lib/multiplex_router.h"
+#include "mojo/public/cpp/bindings/lib/router.h"
+#include "mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.h"
+#include "mojo/public/cpp/system/core.h"
+
+namespace mojo {
+namespace internal {
+
+template <typename Interface, bool use_multiplex_router>
+class BindingState;
+
+// Uses a single-threaded, dedicated router. If |Interface| doesn't have any
+// methods to pass associated interface pointers or requests, there won't be
+// multiple interfaces running on the underlying message pipe. In that case, we
+// can use this specialization to reduce cost.
+template <typename Interface>
+class BindingState<Interface, false> {
+ public:
+  explicit BindingState(Interface* impl) : impl_(impl) {
+    stub_.set_sink(impl_);
+  }
+
+  ~BindingState() {
+    if (router_)
+      Close();
+  }
+
+  void Bind(ScopedMessagePipeHandle handle, const MojoAsyncWaiter* waiter) {
+    DCHECK(!router_);
+    internal::FilterChain filters;
+    filters.Append<internal::MessageHeaderValidator>();
+    filters.Append<typename Interface::RequestValidator_>();
+
+    router_ = new internal::Router(handle.Pass(), filters.Pass(), waiter);
+    router_->set_incoming_receiver(&stub_);
+    router_->set_connection_error_handler(
+        [this]() { connection_error_handler_.Run(); });
+  }
+
+  void PauseIncomingMethodCallProcessing() {
+    DCHECK(router_);
+    router_->PauseIncomingMethodCallProcessing();
+  }
+  void ResumeIncomingMethodCallProcessing() {
+    DCHECK(router_);
+    router_->ResumeIncomingMethodCallProcessing();
+  }
+
+  bool WaitForIncomingMethodCall(
+      MojoDeadline deadline = MOJO_DEADLINE_INDEFINITE) {
+    DCHECK(router_);
+    return router_->WaitForIncomingMessage(deadline);
+  }
+
+  void Close() {
+    DCHECK(router_);
+    router_->CloseMessagePipe();
+    DestroyRouter();
+  }
+
+  InterfaceRequest<Interface> Unbind() {
+    InterfaceRequest<Interface> request =
+        MakeRequest<Interface>(router_->PassMessagePipe());
+    DestroyRouter();
+    return request.Pass();
+  }
+
+  void set_connection_error_handler(const Closure& error_handler) {
+    connection_error_handler_ = error_handler;
+  }
+
+  Interface* impl() { return impl_; }
+
+  bool is_bound() const { return !!router_; }
+
+  MessagePipeHandle handle() const {
+    DCHECK(is_bound());
+    return router_->handle();
+  }
+
+  AssociatedGroup* associated_group() { return nullptr; }
+
+  void EnableTestingMode() {
+    DCHECK(is_bound());
+    router_->EnableTestingMode();
+  }
+
+ private:
+  void DestroyRouter() {
+    router_->set_connection_error_handler(Closure());
+    delete router_;
+    router_ = nullptr;
+  }
+
+  internal::Router* router_ = nullptr;
+  typename Interface::Stub_ stub_;
+  Interface* impl_;
+  Closure connection_error_handler_;
+
+  DISALLOW_COPY_AND_ASSIGN(BindingState);
+};
+
+// Uses a multiplexing router. If |Interface| has methods to pass associated
+// interface pointers or requests, this specialization should be used.
+template <typename Interface>
+class BindingState<Interface, true> {
+ public:
+  explicit BindingState(Interface* impl) : impl_(impl) {
+    stub_.set_sink(impl_);
+  }
+
+  ~BindingState() {
+    if (router_)
+      Close();
+  }
+
+  void Bind(ScopedMessagePipeHandle handle, const MojoAsyncWaiter* waiter) {
+    DCHECK(!router_);
+
+    router_ = new internal::MultiplexRouter(false, handle.Pass(), waiter);
+    endpoint_client_.reset(new internal::InterfaceEndpointClient(
+        router_->CreateLocalEndpointHandle(internal::kMasterInterfaceId),
+        &stub_, make_scoped_ptr(new typename Interface::RequestValidator_())));
+
+    endpoint_client_->set_connection_error_handler(
+        [this]() { connection_error_handler_.Run(); });
+  }
+
+  void Close() {
+    DCHECK(router_);
+    endpoint_client_.reset();
+    router_->CloseMessagePipe();
+    router_ = nullptr;
+  }
+
+  InterfaceRequest<Interface> Unbind() {
+    endpoint_client_.reset();
+    InterfaceRequest<Interface> request =
+        MakeRequest<Interface>(router_->PassMessagePipe());
+    router_ = nullptr;
+    return request.Pass();
+  }
+
+  void set_connection_error_handler(const Closure& error_handler) {
+    connection_error_handler_ = error_handler;
+  }
+
+  Interface* impl() { return impl_; }
+
+  bool is_bound() const { return !!router_; }
+
+  MessagePipeHandle handle() const {
+    DCHECK(is_bound());
+    return router_->handle();
+  }
+
+  AssociatedGroup* associated_group() {
+    return endpoint_client_ ? endpoint_client_->associated_group() : nullptr;
+  }
+
+  void EnableTestingMode() {
+    DCHECK(is_bound());
+    router_->EnableTestingMode();
+  }
+
+  // Intentionally not defined:
+  // void PauseIncomingMethodCallProcessing();
+  // void ResumeIncomingMethodCallProcessing();
+  // bool WaitForIncomingMethodCall(MojoDeadline deadline);
+
+ private:
+  scoped_refptr<internal::MultiplexRouter> router_;
+  scoped_ptr<internal::InterfaceEndpointClient> endpoint_client_;
+
+  typename Interface::Stub_ stub_;
+  Interface* impl_;
+  Closure connection_error_handler_;
+
+  DISALLOW_COPY_AND_ASSIGN(BindingState);
+};
+
+}  // namesapce internal
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDING_STATE_H_