media: Verify CDM Host files

content/common/media/cdm_host_file.h

+// Copyright 2016 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 CONTENT_COMMON_MEDIA_CDM_HOST_FILE_H_
+#define CONTENT_COMMON_MEDIA_CDM_HOST_FILE_H_
+
+#include <memory>
+
+#include "base/files/file.h"
+#include "base/files/file_path.h"
+#include "base/macros.h"
+
+namespace cdm {
+struct CdmHostFile;
+}
+
+namespace content {
+
+// Represents a single file that participated in hosting the CDM.
+class CdmHostFile {
+ public:
+  // Opens the file at |file_path| and the corresponding signature file. Upon
+  // success, constructs and returns a CdmHostFile object. Otherwise returns
+  // nullptr. The opened files are closed when |this| is destructed.
+  static std::unique_ptr<CdmHostFile> Create(const base::FilePath& file_path);
+
+  cdm::CdmHostFile TakePlatformFile();

[jrummell, 2016/12/16 20:21:30]

Does this take ownership of the File objects? or a copy?

Should it be a unique_ptr<> too?

[xhwang, 2017/01/12 20:15:02]

I can't use a unique_ptr since I need to push the cdm::CdmHostFile into a
vector. That being said I found this confusing as well. I'll see how I can
improve it.

[xhwang, 2017/01/18 06:03:58]

Added comments.

+
+ private:
+  CdmHostFile(const base::FilePath& file_path,
+              base::File file,
+              base::File sig_file);
+
+  base::FilePath file_path_;
+  base::File file_;
+
+  // The signature file associated with |file_|.
+  base::File sig_file_;
+
+  DISALLOW_COPY_AND_ASSIGN(CdmHostFile);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_MEDIA_CDM_HOST_FILE_H_