color: Read all displays' color profiles on Windows

ui/display/win/color_profile_reader.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/win/color_profile_reader.h"
+
+#include <stddef.h>
+#include <windows.h>
+
+#include "base/files/file_util.h"
+#include "base/task_scheduler/post_task.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "ui/display/win/display_info.h"
+#include "ui/gfx/icc_profile.h"
+
+namespace display {
+namespace win {
+namespace {
+
+BOOL CALLBACK EnumMonitorCallback(HMONITOR monitor,
+                                  HDC input_hdc,
+                                  LPRECT rect,
+                                  LPARAM data) {
+  base::string16 device_name;
+  MONITORINFOEX monitor_info;
+  ::ZeroMemory(&monitor_info, sizeof(monitor_info));
+  monitor_info.cbSize = sizeof(monitor_info);
+  ::GetMonitorInfo(monitor, &monitor_info);
+  device_name = base::string16(monitor_info.szDevice);
+
+  base::string16 profile_path;
+  HDC hdc = ::CreateDC(monitor_info.szDevice, NULL, NULL, NULL);
+  if (hdc) {
+    DWORD path_length = MAX_PATH;
+    WCHAR path[MAX_PATH + 1];
+    BOOL result = ::GetICMProfile(hdc, &path_length, path);
+    ::DeleteDC(hdc);
+    if (result)
+      profile_path = base::string16(path);
+  }
+
+  std::map<base::string16, base::string16>* device_to_path_map =
+      reinterpret_cast<std::map<base::string16, base::string16>*>(data);
+  (*device_to_path_map)[device_name] = profile_path;
+  return TRUE;
+}
+
+}  // namespace
+
+ColorProfileReader::ColorProfileReader(Client* client)
+    : client_(client), weak_factory_(this) {}
+
+ColorProfileReader::~ColorProfileReader() {}
+
+void ColorProfileReader::UpdateIfNeeded() {
+  if (update_in_flight_)
+    return;
+
+  DeviceToPathMap new_device_to_path_map = BuildDeviceToPathMap();
+  if (device_to_path_map_ == new_device_to_path_map)
+    return;
+
+  if (!base::SequencedWorkerPool::IsEnabled())
+    return;
+
+  update_in_flight_ = true;
+  base::PostTaskWithTraitsAndReplyWithResult(
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
+      base::Bind(&ColorProfileReader::ReadProfilesOnBackgroundThread,
+                 new_device_to_path_map),
+      base::Bind(&ColorProfileReader::ReadProfilesCompleted,
+                 weak_factory_.GetWeakPtr()));
+}
+
+// static
+ColorProfileReader::DeviceToPathMap ColorProfileReader::BuildDeviceToPathMap() {
+  DeviceToPathMap device_to_path_map;
+  EnumDisplayMonitors(nullptr, nullptr, EnumMonitorCallback,
+                      reinterpret_cast<LPARAM>(&device_to_path_map));
+  return device_to_path_map;
+}
+
+// static
+ColorProfileReader::DeviceToDataMap
+ColorProfileReader::ReadProfilesOnBackgroundThread(
+    DeviceToPathMap new_device_to_path_map) {
+  DeviceToDataMap new_device_to_data_map;
+  for (auto entry : new_device_to_path_map) {
+    const base::string16& device_name = entry.first;
+    const base::string16& profile_path = entry.second;
+    std::string profile_data;
+    base::ReadFileToString(base::FilePath(profile_path), &profile_data);
+    new_device_to_data_map[device_name] = profile_data;
+  }
+  return new_device_to_data_map;
+}
+
+void ColorProfileReader::ReadProfilesCompleted(
+    DeviceToDataMap device_to_data_map) {
+  DCHECK(update_in_flight_);
+  update_in_flight_ = false;
+
+  display_id_to_color_space_map_.clear();
+  for (auto entry : device_to_data_map) {
+    const base::string16& device_name = entry.first;
+    const std::string& profile_data = entry.second;
+    int64_t display_id =
+        DisplayInfo::DeviceIdFromDeviceName(device_name.c_str());
+
+    if (profile_data.empty()) {
+      display_id_to_color_space_map_[display_id] = default_color_space_;
+    } else {
+      display_id_to_color_space_map_[display_id] =
+          gfx::ICCProfile::FromData(profile_data.data(), profile_data.size())
+              .GetColorSpace();
+    }
+  }
+
+  client_->OnColorProfilesChanged();
+}
+
+const gfx::ColorSpace& ColorProfileReader::GetDisplayColorSpace(
+    int64_t display_id) const {
+  auto found = display_id_to_color_space_map_.find(display_id);
+  if (found == display_id_to_color_space_map_.end())
+    return default_color_space_;
+  return found->second;
+}
+
+}  // namespace win
+}  // namespace display