src/chrome/browser/chromeos/drive/fileapi/webkit_file_stream_reader_impl.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_READER_IMPL_H_
   6 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_READER_IMPL_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/files/file_path.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "base/time/time.h"
  14 #include "chrome/browser/chromeos/drive/drive_file_stream_reader.h"
  15 #include "net/base/completion_callback.h"
  16 #include "storage/browser/blob/file_stream_reader.h"
  17
  18 namespace base {
  19 class SequencedTaskRunner;
  20 }  // namespace base
  21
  22 namespace drive {
  23
  24 class ResourceEntry;
  25
  26 namespace internal {
  27
  28 // The implementation of storage::FileStreamReader for drive file system.
  29 // storage::FileStreamReader does not provide a way for explicit
  30 // initialization, hence the initialization of this class will be done lazily.
  31 // Note that when crbug.com/225339 is resolved, this class will be also
  32 // initialized explicitly.
  33 class WebkitFileStreamReaderImpl : public storage::FileStreamReader {
  34  public:
  35   WebkitFileStreamReaderImpl(
  36       const DriveFileStreamReader::FileSystemGetter& file_system_getter,
  37       base::SequencedTaskRunner* file_task_runner,
  38       const base::FilePath& drive_file_path,
  39       int64 offset,
  40       const base::Time& expected_modification_time);
  41   virtual ~WebkitFileStreamReaderImpl();
  42
  43   // storage::FileStreamReader override.
  44   virtual int Read(net::IOBuffer* buffer,
  45                    int buffer_length,
  46                    const net::CompletionCallback& callback) override;
  47   virtual int64 GetLength(const net::Int64CompletionCallback& callback)
  48       override;
  49
  50  private:
  51   // Called upon the initialization completion of |stream_reader_|.
  52   // Processes the result of the initialization with checking last
  53   // modified time, and calls |callback| with net::Error code as its result.
  54   void OnStreamReaderInitialized(
  55       const net::CompletionCallback& callback,
  56       int error,
  57       scoped_ptr<ResourceEntry> entry);
  58
  59   // Part of Read(). Called after all the initialization process is completed.
  60   void ReadAfterStreamReaderInitialized(
  61       scoped_refptr<net::IOBuffer> buffer,
  62       int buffer_length,
  63       const net::CompletionCallback& callback,
  64       int initialization_result);
  65
  66   // Part of GetLength(). Called after all the initialization process is
  67   // completed.
  68   void GetLengthAfterStreamReaderInitialized(
  69       const net::Int64CompletionCallback& callback,
  70       int initialization_result);
  71
  72   scoped_ptr<DriveFileStreamReader> stream_reader_;
  73   const base::FilePath drive_file_path_;
  74   const int64 offset_;
  75   const base::Time expected_modification_time_;
  76
  77   // This is available only after initialize is done.
  78   int64 file_size_;
  79
  80   // This should remain the last member so it'll be destroyed first and
  81   // invalidate its weak pointers before other members are destroyed.
  82   base::WeakPtrFactory<WebkitFileStreamReaderImpl> weak_ptr_factory_;
  83   DISALLOW_COPY_AND_ASSIGN(WebkitFileStreamReaderImpl);
  84 };
  85
  86 }  // namespace internal
  87 }  // namespace drive
  88
  89 #endif  // CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_READER_IMPL_H_