mojo::ArrayTraits: Add Support for Iterators

ui/events/mojo/latency_info_struct_traits.cc

 // Copyright 2016 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 "ui/events/mojo/latency_info_struct_traits.h"
 
 #include "ipc/ipc_message_utils.h"
 
 namespace mojo {
 
@@ skipping 218 matching lines @@
 // static
 bool StructTraits<ui::mojom::LatencyComponentId,
                   std::pair<ui::LatencyComponentType, int64_t>>::
     Read(ui::mojom::LatencyComponentIdDataView data,
          std::pair<ui::LatencyComponentType, int64_t>* out) {
   out->first = MojoLatencyComponentTypeToUI(data.type());
   out->second = data.id();
   return true;
 }
 
-void* StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::SetUpContext(
-    const ui::LatencyInfo& info) {
-  // TODO(fsamuel): It would be nice if we had IterableTraits.
-  auto components = new mojo::Array<ui::mojom::LatencyComponentPairPtr>(
-      info.latency_components().size());
-  uint32_t i = 0;
-  for (ui::LatencyInfo::LatencyMap::const_iterator
-           it = info.latency_components().begin();
-       it != info.latency_components().end(); ++it, ++i) {
-    auto latency_component_pair = ui::mojom::LatencyComponentPair::New();
-    latency_component_pair->key = it->first;
-    latency_component_pair->value = it->second;
-    (*components)[i] = std::move(latency_component_pair);
-  }
-  return components;
-}
-
-void StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::TearDownContext(
-    const ui::LatencyInfo& info,
-    void* context) {
-  // static_cast to ensure destructor is called.
-  delete static_cast<mojo::Array<ui::mojom::LatencyComponentPairPtr>*>(context);
-}
-
 // static
 const std::string&
 StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::trace_name(
     const ui::LatencyInfo& info) {
   return info.trace_name_;
 }
 
-// static
-mojo::Array<ui::mojom::LatencyComponentPairPtr>&
+const ui::LatencyInfo::LatencyMap&
 StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::latency_components(
-    const ui::LatencyInfo& info,
-    void* context) {
-  return *static_cast<mojo::Array<ui::mojom::LatencyComponentPairPtr>*>(
-      context);
+    const ui::LatencyInfo& info) {
+  return info.latency_components();
 }
-
 InputCoordinateArray
 StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::input_coordinates(
     const ui::LatencyInfo& info) {
   return {info.input_coordinates_size_, ui::LatencyInfo::kMaxInputCoordinates,
           const_cast<gfx::PointF*>(info.input_coordinates_)};
 }
 
 int64_t StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::trace_id(
     const ui::LatencyInfo& info) {
   return info.trace_id();
 }
 
 bool StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::coalesced(
     const ui::LatencyInfo& info) {
   return info.coalesced();
 }
 
 bool StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::terminated(
     const ui::LatencyInfo& info) {
   return info.terminated();
 }
 
 bool StructTraits<ui::mojom::LatencyInfo, ui::LatencyInfo>::Read(
     ui::mojom::LatencyInfoDataView data,
     ui::LatencyInfo* out) {
   if (!data.ReadTraceName(&out->trace_name_))
     return false;
 
+  // TODO(fsamuel): Figure out how to optimize deserialization.
   mojo::Array<ui::mojom::LatencyComponentPairPtr> components;
   if (!data.ReadLatencyComponents(&components))
     return false;
   for (uint32_t i = 0; i < components.size(); ++i)
     out->latency_components_[components[i]->key] = components[i]->value;
 
   InputCoordinateArray input_coordinate_array = {
       0, ui::LatencyInfo::kMaxInputCoordinates, out->input_coordinates_};
   if (!data.ReadInputCoordinates(&input_coordinate_array))
     return false;
   // TODO(fsamuel): ui::LatencyInfo::input_coordinates_size_ should be a size_t.
   out->input_coordinates_size_ =
       static_cast<uint32_t>(input_coordinate_array.size);
 
   out->trace_id_ = data.trace_id();
   out->coalesced_ = data.coalesced();
   out->terminated_ = data.terminated();
   return true;
 }
 
 }  // namespace mojo