webkit/fileapi/file_system_file_stream_reader.h

   1 // Copyright (c) 2012 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 WEBKIT_FILEAPI_FILE_SYSTEM_FILE_STREAM_READER_H_
   6 #define WEBKIT_FILEAPI_FILE_SYSTEM_FILE_STREAM_READER_H_
   7
   8 #include "base/bind.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/platform_file.h"
  11 #include "webkit/fileapi/file_system_url.h"
  12 #include "webkit/blob/file_stream_reader.h"
  13 #include "webkit/blob/shareable_file_reference.h"
  14
  15 class FilePath;
  16
  17 namespace base {
  18 class SequencedTaskRunner;
  19 }
  20
  21 namespace webkit_blob {
  22 class LocalFileStreamReader;
  23 }
  24
  25 namespace fileapi {
  26
  27 class FileSystemContext;
  28
  29 // TODO(kinaba,satorux): This generic implementation would work for any
  30 // filesystems but remote filesystem should implement its own reader
  31 // rather than relying on FileSystemOperation::GetSnapshotFile() which
  32 // may force downloading the entire contents for remote files.
  33 class FileSystemFileStreamReader : public webkit_blob::FileStreamReader {
  34  public:
  35   // Creates a new FileReader for a filesystem URL |url| form |initial_offset|.
  36   FileSystemFileStreamReader(FileSystemContext* file_system_context,
  37                              const FileSystemURL& url,
  38                              int64 initial_offset);
  39   virtual ~FileSystemFileStreamReader();
  40
  41   // FileReader override.
  42   virtual int Read(net::IOBuffer* buf, int buf_len,
  43                    const net::CompletionCallback& callback) OVERRIDE;
  44
  45  private:
  46   void DidCreateSnapshot(
  47       const base::Closure& read_closure,
  48       const net::CompletionCallback& callback,
  49       base::PlatformFileError file_error,
  50       const base::PlatformFileInfo& file_info,
  51       const FilePath& platform_path,
  52       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
  53
  54   scoped_refptr<FileSystemContext> file_system_context_;
  55   FileSystemURL url_;
  56   const int64 initial_offset_;
  57   scoped_ptr<webkit_blob::LocalFileStreamReader> local_file_reader_;
  58   scoped_refptr<webkit_blob::ShareableFileReference> snapshot_ref_;
  59   bool has_pending_create_snapshot_;
  60   base::WeakPtrFactory<FileSystemFileStreamReader> weak_factory_;
  61
  62   DISALLOW_COPY_AND_ASSIGN(FileSystemFileStreamReader);
  63 };
  64
  65 }  // namespace fileapi
  66
  67 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_FILE_STREAM_READER_H_