Implement ScopedFD in terms of ScopedGeneric.

base/files/scoped_file.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 BASE_FILES_SCOPED_FILE_H_
+#define BASE_FILES_SCOPED_FILE_H_
+
+#include <stdio.h>
+
+#include "base/base_export.h"
+#include "base/logging.h"
+#include "base/scoped_generic.h"
+#include "build/build_config.h"
+
+namespace base {
+
+namespace internal {
+
+#if defined(OS_POSIX)
+struct BASE_EXPORT ScopedFDCloseTraits {
+  static int InvalidValue() {
+    return -1;
+  }
+  static void Free(int fd);
+};
+#endif
+
+}  // namespace internal
+
+#if defined(OS_POSIX)
+// A low-level Posix file descriptor closer class. Use this when writing
+// platform-specific code, especially that does non-file-like things with the
+// FD (like sockets).
+//
+// If you're writing low-level Windows code, see base/win/scoped_handle.h
+// which provides some additional functionality.
+//
+// If you're writing cross-platform code that deals with actual files, you
+// should generally use base::File instead which can be constructed with a
+// handle, and in addition to handling ownership, has convenient cross-platform
+// file manipulation functions on it.
+typedef ScopedGeneric<int, internal::ScopedFDCloseTraits> ScopedFD;
+#endif
+
+}  // namespace base
+
+#endif  // BASE_FILES_SCOPED_FILE_H_