storage/browser/fileapi/quota/open_file_handle_context.h

   1 // Copyright 2013 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 STORAGE_BROWSER_FILEAPI_OPEN_FILE_HANDLE_CONTEXT_H_
   6 #define STORAGE_BROWSER_FILEAPI_OPEN_FILE_HANDLE_CONTEXT_H_
   7
   8 #include <map>
   9
  10 #include "base/basictypes.h"
  11 #include "base/files/file_path.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "storage/browser/storage_browser_export.h"
  15 #include "storage/common/fileapi/file_system_types.h"
  16 #include "url/gurl.h"
  17
  18 namespace storage {
  19
  20 class QuotaReservationBuffer;
  21
  22 // This class represents a underlying file of a managed FileSystem file.
  23 // The instance keeps alive while at least one consumer keeps an open file
  24 // handle.
  25 // This class is usually manipulated only via OpenFileHandle.
  26 class OpenFileHandleContext : public base::RefCounted<OpenFileHandleContext> {
  27  public:
  28   OpenFileHandleContext(const base::FilePath& platform_path,
  29                         QuotaReservationBuffer* reservation_buffer);
  30
  31   // Updates the max written offset and returns the amount of growth.
  32   int64 UpdateMaxWrittenOffset(int64 offset);
  33
  34   void AddAppendModeWriteAmount(int64 amount);
  35
  36   const base::FilePath& platform_path() const {
  37     return platform_path_;
  38   }
  39
  40   int64 GetEstimatedFileSize() const;
  41   int64 GetMaxWrittenOffset() const;
  42
  43  private:
  44   friend class base::RefCounted<OpenFileHandleContext>;
  45   virtual ~OpenFileHandleContext();
  46
  47   int64 initial_file_size_;
  48   int64 maximum_written_offset_;
  49   int64 append_mode_write_amount_;
  50   base::FilePath platform_path_;
  51
  52   scoped_refptr<QuotaReservationBuffer> reservation_buffer_;
  53
  54   base::SequenceChecker sequence_checker_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(OpenFileHandleContext);
  57 };
  58
  59 }  // namespace storage
  60
  61 #endif  // STORAGE_BROWSER_FILEAPI_OPEN_FILE_HANDLE_CONTEXT_H_