src/storage/browser/fileapi/local_file_stream_writer.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 STORAGE_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_
   6 #define STORAGE_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_
   7
   8 #include <utility>
   9
  10 #include "base/callback.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/files/file_path.h"
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "base/task_runner.h"
  17 #include "storage/browser/fileapi/file_stream_writer.h"
  18 #include "storage/browser/storage_browser_export.h"
  19
  20 namespace content {
  21 class LocalFileStreamWriterTest;
  22 }
  23
  24 namespace net {
  25 class FileStream;
  26 }
  27
  28 namespace storage {
  29
  30 // This class is a thin wrapper around net::FileStream for writing local files.
  31 class STORAGE_EXPORT LocalFileStreamWriter
  32     : public NON_EXPORTED_BASE(FileStreamWriter) {
  33  public:
  34   virtual ~LocalFileStreamWriter();
  35
  36   // FileStreamWriter overrides.
  37   virtual int Write(net::IOBuffer* buf, int buf_len,
  38                     const net::CompletionCallback& callback) OVERRIDE;
  39   virtual int Cancel(const net::CompletionCallback& callback) OVERRIDE;
  40   virtual int Flush(const net::CompletionCallback& callback) OVERRIDE;
  41
  42  private:
  43   friend class content::LocalFileStreamWriterTest;
  44   friend class FileStreamWriter;
  45   LocalFileStreamWriter(base::TaskRunner* task_runner,
  46                         const base::FilePath& file_path,
  47                         int64 initial_offset,
  48                         OpenOrCreate open_or_create);
  49
  50   // Opens |file_path_| and if it succeeds, proceeds to InitiateSeek().
  51   // If failed, the error code is returned by calling |error_callback|.
  52   int InitiateOpen(const net::CompletionCallback& error_callback,
  53                    const base::Closure& main_operation);
  54   void DidOpen(const net::CompletionCallback& error_callback,
  55                const base::Closure& main_operation,
  56                int result);
  57
  58   // Seeks to |initial_offset_| and proceeds to |main_operation| if it succeeds.
  59   // If failed, the error code is returned by calling |error_callback|.
  60   void InitiateSeek(const net::CompletionCallback& error_callback,
  61                     const base::Closure& main_operation);
  62   void DidSeek(const net::CompletionCallback& error_callback,
  63                const base::Closure& main_operation,
  64                int64 result);
  65
  66   // Passed as the |main_operation| of InitiateOpen() function.
  67   void ReadyToWrite(net::IOBuffer* buf, int buf_len,
  68                     const net::CompletionCallback& callback);
  69
  70   // Writes asynchronously to the file.
  71   int InitiateWrite(net::IOBuffer* buf, int buf_len,
  72                     const net::CompletionCallback& callback);
  73   void DidWrite(const net::CompletionCallback& callback, int result);
  74
  75   // Flushes asynchronously to the file.
  76   int InitiateFlush(const net::CompletionCallback& callback);
  77   void DidFlush(const net::CompletionCallback& callback, int result);
  78
  79   // Stops the in-flight operation and calls |cancel_callback_| if it has been
  80   // set by Cancel() for the current operation.
  81   bool CancelIfRequested();
  82
  83   // Initialization parameters.
  84   const base::FilePath file_path_;
  85   OpenOrCreate open_or_create_;
  86   const int64 initial_offset_;
  87   scoped_refptr<base::TaskRunner> task_runner_;
  88
  89   // Current states of the operation.
  90   bool has_pending_operation_;
  91   scoped_ptr<net::FileStream> stream_impl_;
  92   net::CompletionCallback cancel_callback_;
  93
  94   base::WeakPtrFactory<LocalFileStreamWriter> weak_factory_;
  95   DISALLOW_COPY_AND_ASSIGN(LocalFileStreamWriter);
  96 };
  97
  98 }  // namespace storage
  99
 100 #endif  // STORAGE_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_