Add CDM FileIO tests.

media/cdm/ppapi/cdm_file_io_impl.h

+// Copyright 2013 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 MEDIA_CDM_PPAPI_CDM_FILE_IO_IMPL_H_
+#define MEDIA_CDM_PPAPI_CDM_FILE_IO_IMPL_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "media/cdm/ppapi/api/content_decryption_module.h"
+#include "ppapi/c/ppb_file_io.h"
+#include "ppapi/cpp/file_io.h"
+#include "ppapi/cpp/file_ref.h"
+#include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/module.h"
+#include "ppapi/cpp/private/isolated_file_system_private.h"
+#include "ppapi/utility/completion_callback_factory.h"
+
+namespace media {
+
+// Due to PPAPI limitations, all functions must be called on the main thread.
+class CdmFileIOImpl : public cdm::CdmFileIO {
+ public:
+  CdmFileIOImpl(cdm::CdmFileIOClient* client, PP_Instance pp_instance);
+  virtual ~CdmFileIOImpl();
+
+  // cdm::CdmFileIO implementation.
+  virtual void Open(const char* file_name, uint32_t file_name_size) OVERRIDE;
+  virtual void Read() OVERRIDE;
+  virtual void Write(const uint8_t* data, uint32_t data_size) OVERRIDE;
+  virtual void Close() OVERRIDE;
+
+ private:
+  enum State {
+    OPENING_FILE_SYSTEM,
+    OPENING_FILE,
+    FILE_OPENED,
+    READING_FILE,
+    WRITING_FILE,
+    FILE_CLOSED
+  };
+
+  enum ErrorType {
+    OPEN_ERROR,
+    READ_ERROR,
+    WRITE_ERROR
+  };
+
+  void OpenFileSystem();
+  void OnFileSystemOpen(int32_t result, pp::FileSystem file_system);

[ddorwin, 2013/12/04 05:27:08]

Open_ed_?
ditto at 54.

[xhwang, 2013/12/10 01:24:25]

Done.

+  void OpenFile();
+  void OnFileOpen(int32_t result);
+  void ReadFile();
+  void OnFileRead(int32_t bytes_read);
+  void WriteFile();
+  void OnFileWritten(int32_t bytes_written);
+
+  void CloseFile();
+
+  // Calls client_->OnXxxxComplete with kError asynchronously. In some cases we
+  // could actually call them synchronously, but since these errors shouldn't
+  // happen in normal cases, we are not optimizing these cases.

[ddorwin, 2013/12/04 05:27:08]

nit: s/these/such/ sounds better IMO

[xhwang, 2013/12/10 01:24:25]

Done.

+  void OnError(ErrorType error_type, const std::string& error_msg);
+  // Callback to notify client of error asynchronously.
+  void NotifyClientOfError(int32_t result,
+                           ErrorType error_type,
+                           const std::string& error_msg);
+
+  State state_;
+
+  // Non-owning pointer.
+  cdm::CdmFileIOClient* const client_;
+
+  const pp::InstanceHandle pp_instance_handle_;
+
+  std::string file_name_;
+  pp::FileRef file_ref_;
+  pp::FileIO file_io_;
+  pp::FileSystem file_system_;
+
+  pp::CompletionCallbackFactory<CdmFileIOImpl> callback_factory_;
+
+  // A temporary buffer to hold data to write or the data that has been read.

[ddorwin, 2013/12/04 05:27:08]

If this holds read data, why do we have read_buffer_?

[xhwang, 2013/12/10 01:24:25]

This holds "partial" read/write data. Renamed to io_buffer_ and updated comment.

+  // The size of |buffer_| is always "bytes to write" or "bytes to read".
+  // Use "char" instead of "unit8_t" because PPB_FileIO uses char* for binary
+  // data read and write.
+  std::vector<char> buffer_;

[ddorwin, 2013/12/04 05:27:08]

It seems we should name this such that it's clear it is related to the actual
I/O calls.

[xhwang, 2013/12/10 01:24:25]

Done.

+
+  // Offset into the file for reading/writing data.
+  size_t file_offset_;
+
+  // Buffer to hold all read data requested. This buffer is passed to
+  // |client_| when read completes.
+  std::vector<char> read_buffer_;

[ddorwin, 2013/12/04 05:27:08]

cumulative_read_buffer_? Or something similar to indicate we're collecting from
multiple reads to get the whole file.

[xhwang, 2013/12/10 01:24:25]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(CdmFileIOImpl);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CDM_PPAPI_CDM_FILE_IO_IMPL_H_