Mojo bindings: merge the control messages of sending disconnect reason and notifying endpoint close…

mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.cc

 // 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.
 
 #include "mojo/public/cpp/bindings/scoped_interface_endpoint_handle.h"
 
 #include "base/logging.h"
 #include "mojo/public/cpp/bindings/associated_group_controller.h"
 
 namespace mojo {
@@ skipping 14 matching lines @@
 
 ScopedInterfaceEndpointHandle& ScopedInterfaceEndpointHandle::operator=(
     ScopedInterfaceEndpointHandle&& other) {
   reset();
   swap(other);
 
   return *this;
 }
 
 void ScopedInterfaceEndpointHandle::reset() {
-  if (!IsValidInterfaceId(id_))
-    return;
+  ResetInternal(base::nullopt);
+}
 
-  group_controller_->CloseEndpointHandle(id_, is_local_);
-
-  id_ = kInvalidInterfaceId;
-  is_local_ = true;
-  group_controller_ = nullptr;
+void ScopedInterfaceEndpointHandle::ResetWithReason(
+    uint32_t custom_reason,
+    const std::string& description) {
+  base::Optional<DisconnectReason> reason;
+  reason.emplace(custom_reason, description);
+  ResetInternal(reason);

[dcheng, 2017/01/23 23:20:22]

FWIW, here and a couple other places

ResetInternal(DisconnectReason(custom_reason, description))

would also work and should save a copy.

[yzshen1, 2017/01/23 23:30:09]

I think the original code doesn't copy either. Have I missed anything?

But the change you proposed is more concise. I could make such a change in my
next CL.

[dcheng, 2017/01/24 03:39:21]

Ah, you're right: my comment is only true if |reason| is passed by value instead
of const ref. Sorry!

 }
 
 void ScopedInterfaceEndpointHandle::swap(ScopedInterfaceEndpointHandle& other) {
   using std::swap;
   swap(other.id_, id_);
   swap(other.is_local_, is_local_);
   swap(other.group_controller_, group_controller_);
 }
 
 InterfaceId ScopedInterfaceEndpointHandle::release() {
   InterfaceId result = id_;
 
   id_ = kInvalidInterfaceId;
   is_local_ = true;
   group_controller_ = nullptr;
 
   return result;
 }
 
 ScopedInterfaceEndpointHandle::ScopedInterfaceEndpointHandle(
     InterfaceId id,
     bool is_local,
     scoped_refptr<AssociatedGroupController> group_controller)
     : id_(id),
       is_local_(is_local),
       group_controller_(std::move(group_controller)) {
   DCHECK(!IsValidInterfaceId(id) || group_controller_);
 }
 
+void ScopedInterfaceEndpointHandle::ResetInternal(
+    const base::Optional<DisconnectReason>& reason) {
+  if (!IsValidInterfaceId(id_))
+    return;
+
+  group_controller_->CloseEndpointHandle(id_, is_local_, reason);
+
+  id_ = kInvalidInterfaceId;
+  is_local_ = true;
+  group_controller_ = nullptr;
+}
+
 }  // namespace mojo