Write mojom and StructTraits for DisplaySnapshot.

ui/display/mojo/display_snapshot_mojo_struct_traits.cc

+// Copyright 2017 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/display/mojo/display_snapshot_mojo_struct_traits.h"
+
+#include "ipc/ipc_message_utils.h"

[kylechar, 2017/02/14 21:35:28]

I'm not sure what this is doing here? This is a header with helper functions for
the old style of Chrome IPC.

[thanhph1, 2017/02/15 15:37:55]

|sys_path| mojom serialization and de-serialization use this.

+#include "ui/display/mojo/display_constants_struct_traits.h"
+#include "ui/display/mojo/display_mode_struct_traits.h"
+#include "ui/display/types/display_constants.h"
+#include "ui/gfx/geometry/mojo/geometry_struct_traits.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace mojo {
+
+namespace {
+
+static uint64_t GetModeIndex(
+    const display::DisplaySnapshot::DisplayModeList& modes,
+    const display::DisplayMode* mode) {
+  if (!mode)
+    return -1;

[kylechar, 2017/02/14 21:35:28]

You are returning a negative number as an unsigned integer. That will be
converted to std::numeric_limits<uint64_t>::max() I think, which isn't a bad
value to serialize for nullptr, but it's not really correct to just return -1.

[thanhph1, 2017/02/15 15:37:55]

Agree. I will use std::numeric_limits<uint64_t>::max() then.

+
+  for (size_t i = 0; i < modes.size(); ++i) {
+    if (*modes[i].get() == *mode)
+      return i;
+  }
+  NOTREACHED();
+  return -1;
+}
+
+}  // namespace
+
+// static
+std::vector<std::unique_ptr<display::DisplayMode>>
+StructTraits<display::mojom::DisplaySnapshotMojoDataView,
+             std::unique_ptr<display::DisplaySnapshotMojo>>::
+    modes(
+        const std::unique_ptr<display::DisplaySnapshotMojo>& display_snapshot) {
+  std::vector<std::unique_ptr<display::DisplayMode>> display_mode_list;
+
+  for (const auto& display_mode : display_snapshot->modes())
+    display_mode_list.push_back(display_mode->Clone());
+
+  return display_mode_list;
+}
+
+// static
+uint64_t StructTraits<display::mojom::DisplaySnapshotMojoDataView,
+                      std::unique_ptr<display::DisplaySnapshotMojo>>::
+    current_mode_index(
+        const std::unique_ptr<display::DisplaySnapshotMojo>& display_snapshot) {
+  return GetModeIndex(display_snapshot->modes(),
+                      display_snapshot->current_mode());
+}
+
+// static
+uint64_t StructTraits<display::mojom::DisplaySnapshotMojoDataView,
+                      std::unique_ptr<display::DisplaySnapshotMojo>>::
+    native_mode_index(
+        const std::unique_ptr<display::DisplaySnapshotMojo>& display_snapshot) {
+  return GetModeIndex(display_snapshot->modes(),
+                      display_snapshot->native_mode());
+}
+
+// static
+bool StructTraits<display::mojom::DisplaySnapshotMojoDataView,
+                  std::unique_ptr<display::DisplaySnapshotMojo>>::
+    Read(display::mojom::DisplaySnapshotMojoDataView data,
+         std::unique_ptr<display::DisplaySnapshotMojo>* out) {
+  gfx::Point origin;
+  if (!data.ReadOrigin(&origin))
+    return false;
+
+  gfx::Size physical_size;
+  if (!data.ReadPhysicalSize(&physical_size))
+    return false;
+
+  display::DisplayConnectionType type;
+  if (!data.ReadType(&type))
+    return false;
+
+  std::string display_name;
+  if (!data.ReadDisplayName(&display_name))
+    return false;
+
+  base::FilePath file_path;
+  if (!data.ReadSysPath(&file_path))
+    return false;
+
+  // There is a type mismatch between vectors containing unique_ptr<T> vs
+  // unique_ptr<const T>. We deserialize into a vector of unique_ptr<T>
+  // then create a vector of unique_ptr<const T> after.
+  std::vector<std::unique_ptr<display::DisplayMode>> non_const_modes;
+  if (!data.ReadModes(&non_const_modes))
+    return false;
+  display::DisplaySnapshot::DisplayModeList modes;

[kylechar, 2017/02/14 21:35:28]

display::DisplaySnapshot::DisplayModeList modes(non_const_modes.size());

[thanhph1, 2017/02/15 15:37:55]

This will fail.  I'll keep it as it is.

+  for (auto& mode : non_const_modes)
+    modes.push_back(std::move(mode));
+
+  // Get current_mode pointer from modes array.
+  const display::DisplayMode* current_mode = nullptr;
+  if (data.has_current_mode()) {
+    size_t current_mode_index = data.current_mode_index();
+    if (current_mode_index >= modes.size())
+      return false;
+    current_mode = modes[current_mode_index].get();
+  }
+
+  // Get native_mode pointer from modes array.
+  const display::DisplayMode* native_mode = nullptr;
+  if (data.has_native_mode()) {
+    size_t native_mode_index = data.native_mode_index();
+    if (native_mode_index >= modes.size())
+      return false;
+    native_mode = modes[native_mode_index].get();
+  }
+
+  std::vector<uint8_t> edid;
+  if (!data.ReadEdid(&edid))
+    return false;
+
+  gfx::Size maximum_cursor_size;
+  if (!data.ReadMaximumCursorSize(&maximum_cursor_size))
+    return false;
+
+  *out = base::MakeUnique<display::DisplaySnapshotMojo>(
+      data.display_id(), origin, physical_size, type,
+      data.is_aspect_preserving_scaling(), data.has_overscan(),
+      data.has_color_correction_matrix(), display_name, file_path,
+      data.product_id(), std::move(modes), std::move(edid), current_mode,
+      native_mode, maximum_cursor_size);
+  return true;
+}
+
+}  // namespace mojo