Udev-related methods are extracted from HidServiceLinux into individual service.

device/hid/udev_common.h

+// 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.
+
+#ifndef DEVICE_HID_UDEV_COMMON_H_
+#define DEVICE_HID_UDEV_COMMON_H_
+
+#include <libudev.h>
+
+#include "base/memory/scoped_ptr.h"
+
+namespace device {
+
+template <typename T, void func(T*)>
+void DiscardReturnType(T* arg) {
+  func(arg);
+}
+
+template <typename T, T* func(T*)>
+void DiscardReturnType(T* arg) {
+  func(arg);
+}
+
+template <typename T, void func(T*)>
+struct Deleter {
+  void operator()(T* enumerate) const {
+    if (enumerate != NULL)
+      func(enumerate);
+  }
+};
+
+typedef Deleter<udev, DiscardReturnType<udev, udev_unref> > UdevDeleter;
+typedef Deleter<udev_enumerate,
+                DiscardReturnType<udev_enumerate, udev_enumerate_unref> >
+    UdevEnumerateDeleter;
+typedef Deleter<udev_device, DiscardReturnType<udev_device, udev_device_unref> >
+    UdevDeviceDeleter;
+typedef Deleter<udev_monitor,
+                DiscardReturnType<udev_monitor, udev_monitor_unref> >
+    UdevMonitorDeleter;
+
+typedef scoped_ptr<udev, UdevDeleter> ScopedUdevPtr;
+typedef scoped_ptr<udev_enumerate, UdevEnumerateDeleter> ScopedUdevEnumeratePtr;
+typedef scoped_ptr<udev_device, UdevDeviceDeleter> ScopedUdevDevicePtr;
+typedef scoped_ptr<udev_monitor, UdevMonitorDeleter> ScopedUdevMonitorPtr;
+
+}  // namespace device
+
+#endif  // DEVICE_HID_UDEV_COMMON_H_