Sync ui/events to chromium @ https://codereview.chromium.org/1210203002

ui/events/devices/device_util_linux.cc

+// Copyright 2014 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/devices/device_util_linux.h"
+
+#include <string>
+
+#include "base/files/file_enumerator.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/message_loop/message_loop.h"
+#include "base/strings/string_util.h"
+
+namespace ui {
+
+InputDeviceType GetInputDeviceTypeFromPath(const base::FilePath& path) {
+  DCHECK(!base::MessageLoopForUI::IsCurrent());
+  std::string event_node = path.BaseName().value();
+  if (event_node.empty() || !StartsWithASCII(event_node, "event", false))
+    return InputDeviceType::INPUT_DEVICE_UNKNOWN;
+
+  // Find sysfs device path for this device.
+  base::FilePath sysfs_path =
+      base::FilePath(FILE_PATH_LITERAL("/sys/class/input"));
+  sysfs_path = sysfs_path.Append(path.BaseName());
+  sysfs_path = base::MakeAbsoluteFilePath(sysfs_path);
+
+  // Device does not exist.
+  if (sysfs_path.empty())
+    return InputDeviceType::INPUT_DEVICE_UNKNOWN;
+
+  // Check ancestor devices for a known bus attachment.
+  for (base::FilePath path = sysfs_path; path != base::FilePath("/");
+       path = path.DirName()) {
+    // Bluetooth LE devices are virtual "uhid" devices.
+    if (path ==
+        base::FilePath(FILE_PATH_LITERAL("/sys/devices/virtual/misc/uhid")))
+      return InputDeviceType::INPUT_DEVICE_EXTERNAL;
+
+    std::string subsystem_path =
+        base::MakeAbsoluteFilePath(path.Append(FILE_PATH_LITERAL("subsystem")))
+            .value();
+    if (subsystem_path.empty())
+      continue;
+
+    // Internal bus attachments.
+    if (subsystem_path == "/sys/bus/pci")
+      return InputDeviceType::INPUT_DEVICE_INTERNAL;
+    if (subsystem_path == "/sys/bus/i2c")
+      return InputDeviceType::INPUT_DEVICE_INTERNAL;
+    if (subsystem_path == "/sys/bus/acpi")
+      return InputDeviceType::INPUT_DEVICE_INTERNAL;
+    if (subsystem_path == "/sys/bus/serio")
+      return InputDeviceType::INPUT_DEVICE_INTERNAL;
+    if (subsystem_path == "/sys/bus/platform")
+      return InputDeviceType::INPUT_DEVICE_INTERNAL;
+
+    // External bus attachments.
+    if (subsystem_path == "/sys/bus/usb")
+      return InputDeviceType::INPUT_DEVICE_EXTERNAL;
+    if (subsystem_path == "/sys/class/bluetooth")
+      return InputDeviceType::INPUT_DEVICE_EXTERNAL;
+  }
+
+  return InputDeviceType::INPUT_DEVICE_UNKNOWN;
+}
+
+}  // namespace