Mojo C++ bindings: support disconnect with a reason.

mojo/public/cpp/bindings/associated_binding.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_ASSOCIATED_BINDING_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_ASSOCIATED_BINDING_H_
 
 #include <memory>
+#include <string>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "mojo/public/cpp/bindings/associated_group.h"
 #include "mojo/public/cpp/bindings/associated_group_controller.h"
 #include "mojo/public/cpp/bindings/associated_interface_request.h"
+#include "mojo/public/cpp/bindings/connection_error_callback.h"
 #include "mojo/public/cpp/bindings/interface_endpoint_client.h"
 #include "mojo/public/cpp/bindings/lib/control_message_proxy.h"
 #include "mojo/public/cpp/bindings/scoped_interface_endpoint_handle.h"
 
 namespace mojo {
 
 class MessageReceiver;
 
 // Represents the implementation side of an associated interface. It is similar
 // to Binding, except that it doesn't own a message pipe handle.
@@ skipping 67 matching lines @@
 
     if (!handle.is_valid() || !handle.is_local()) {
       endpoint_client_.reset();
       return;
     }
 
     endpoint_client_.reset(new InterfaceEndpointClient(
         std::move(handle), &stub_,
         base::WrapUnique(new typename Interface::RequestValidator_()),
         Interface::HasSyncMethods_, std::move(runner), Interface::Version_));
-    endpoint_client_->set_connection_error_handler(
-        base::Bind(&AssociatedBinding::RunConnectionErrorHandler,
-                   base::Unretained(this)));
 
     stub_.serialization_context()->group_controller =
         endpoint_client_->group_controller();
   }
 
   // Adds a message filter to be notified of each incoming message before
   // dispatch. If a filter returns |false| from Accept(), the message is not
   // dispatched and the pipe is closed. Filters cannot be removed.
   void AddFilter(std::unique_ptr<MessageReceiver> filter) {
     DCHECK(endpoint_client_);
     endpoint_client_->AddFilter(std::move(filter));
   }
 
   // Closes the associated interface. Puts this object into a state where it can
   // be rebound.
   void Close() {
     DCHECK(endpoint_client_);
     endpoint_client_.reset();
-    connection_error_handler_.Reset();
+  }
+
+  // Similar to the method above, but also specifies a disconnect reason.
+  void CloseWithReason(uint32_t custom_reason, const std::string& description) {
+    DCHECK(endpoint_client_);
+    endpoint_client_->control_message_proxy()->SendDisconnectReason(
+        custom_reason, description);
+    Close();
   }
 
   // Unbinds and returns the associated interface request so it can be
   // used in another context, such as on another thread or with a different
   // implementation. Puts this object into a state where it can be rebound.
   AssociatedInterfaceRequest<Interface> Unbind() {
     DCHECK(endpoint_client_);
 
     AssociatedInterfaceRequest<Interface> request;
     request.Bind(endpoint_client_->PassHandle());
 
     endpoint_client_.reset();
-    connection_error_handler_.Reset();
 
     return request;
   }
 
   // Sets an error handler that will be called if a connection error occurs.
   //
   // This method may only be called after this AssociatedBinding has been bound
   // to a message pipe. The error handler will be reset when this
   // AssociatedBinding is unbound or closed.
   void set_connection_error_handler(const base::Closure& error_handler) {
     DCHECK(is_bound());
-    connection_error_handler_ = error_handler;
+    endpoint_client_->set_connection_error_handler(error_handler);
+  }
+
+  void set_connection_error_with_reason_handler(
+      const ConnectionErrorWithReasonCallback& error_handler) {
+    DCHECK(is_bound());
+    endpoint_client_->set_connection_error_with_reason_handler(error_handler);
   }
 
   // Returns the interface implementation that was previously specified.
   Interface* impl() { return impl_; }
 
   // Indicates whether the associated binding has been completed.
   bool is_bound() const { return !!endpoint_client_; }
 
   // Returns the associated group that this object belongs to. Returns null if
   // the object is not bound.
   AssociatedGroup* associated_group() {
     return endpoint_client_ ? endpoint_client_->associated_group() : nullptr;
   }
 
   // Sends a message on the underlying message pipe and runs the current
   // message loop until its response is received. This can be used in tests to
   // verify that no message was sent on a message pipe in response to some
   // stimulus.
   void FlushForTesting() {
     endpoint_client_->control_message_proxy()->FlushForTesting();
   }
 
  private:
-  void RunConnectionErrorHandler() {
-    if (!connection_error_handler_.is_null())
-      connection_error_handler_.Run();
-  }
-
   std::unique_ptr<InterfaceEndpointClient> endpoint_client_;
 
   typename Interface::Stub_ stub_;
   Interface* impl_;
-  base::Closure connection_error_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(AssociatedBinding);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_ASSOCIATED_BINDING_H_